Voice over data telecommunications network architecture

[0001] This application is a continuation of U.S. patent application Ser. No. 09/197,203, entitled VOICE OVER DATA TELECOMMUNICATION NETWORK ARCHITECTURE, filed Nov. 20, 1998, now U.S. Pat. No. 6,614,781. This application of common assignee contains a related disclosure to U.S. Pat. No. 6,442,169, entitled “System and Method for Bypassing Data from Egress Facilities.” Both U.S. patent application Ser. No. 09/197,203 and U.S. Pat. No. 6,442,169 are incorporated herein by reference in their entirety.

[0002] 1. Field of the Invention

[0003] The present invention relates generally to telecommunications networks and, more particularly, to a system and method for providing transmission for voice and data traffic over a data network, including the signaling, routing and manipulation of such traffic.

[0004] 2. Related Art

[0005] The present invention relates to telecommunications, and in particular to voice and data communication operating over a data network. The Public Switched Telephone Network (PSTN) is a collection of different telephone networks owned by different companies which have for many years provided telephone communication between users of the network. Different parts of the PSTN network use different transmission media and compression techniques.

[0006] Most long distance calls are digitally coded and transmitted along a transmission line such as a T1 line or fiber optic cable, using circuit switching technology to transmit the calls. Such calls are time division multiplexed (TDM) into separate channels, which allow many calls to pass over the lines without interacting. The channels are directed independently through multiple circuit switches from an originating switch to a destination switch. Using conventional circuit switched communications, a channel on each of the T1 lines along which a call is transmitted is dedicated for the duration of the call, whether or not any information is actually being transmitted over the channel. The set of channels being used by the call is referred to as a “circuit.”

[0007] Telecommunications networks were originally designed to connect one device, such as a telephone, to another device, such as a telephone, using switching services. As previously mentioned, circuit-switched networks provide a dedicated, fixed amount of capacity (a “circuit”) between the two devices for the entire duration of a transmission session. Originally, this was accomplished manually. A human operator would physically patch a wire between two sockets to form a direct connection from the calling party to the called party. More recently, a circuit is set up between an originating switch and a destination switch using a process known as signaling.

[0008] Signaling sets up, monitors, and releases connections in a circuit-switched system. Various signaling methods have been devised. Telephone systems formerly used in-band signaling to set up and tear down calls. Signals of an in-band signaling system are passed through the same channels as the information being transmitted. Early electromechanical switches used analog or multi-frequency (MF) in-band signaling. Thereafter, conventional residential telephones used in-band dual-tone multiple frequency (DTMF) signaling to connect to an end office switch. Here, the same wires (and frequencies on the wires) were used to dial a number (using pulses or tones), as are used to transmit voice information. However, in-band signaling permitted unscrupulous callers to use a device such as a whistle to mimic signaling sounds to commit fraud (e.g., to prematurely discontinue billing by an interexchange carrier (IXC), also known as a long distance telephone company).

[0009] More recently, to prevent such fraud, out-of-band signaling systems were introduced. Out-of-band signaling uses a signaling network that is separate from the circuit switched network used for carrying the actual call information. For example, integrated services digital network (ISDN) uses a separate channel, a data (D) channel, to pass signaling information out-of-band. Common Channel Interoffice Signaling (CCIS) is another network architecture for out-of-band signaling. A popular version of CCIS signaling is Signaling System 7 (SS7). SS7 is an internationally recognized system optimized for use in digital telecommunications networks.

[0010] SS7 out-of-band signaling provided additional benefits beyond fraud prevention. For example, out-of-band signaling eased quick adoption of advanced features (e.g., caller id) by permitting modifications to the separate signaling network. In addition, the SS7 network enabled long distance “Equal Access” (i.e., 1+ dialing for access to any long distance carrier) as required under the terms of the modified final judgment (MFJ) requiring divestiture of the Regional Bell Operating Companies (RBOCs) from their parent company, AT&T.

[0011] An SS7 network is a packet-switched signaling network formed from a variety of components, including Service Switching Points (SSPs), Signaling Transfer Points (STPs) and Service Control Points (SCPs). An SSP is a telephone switch which is directly connected to an SS7 network. All calls must originate in or be routed through an SSP. Calls are passed through connections between SSPs. An SCP is a special application computer which maintains information in a database required by users of the network. SCP databases may include, for example, a credit card database for verifying charge information or an “800” database for processing number translations for toll-free calls. STPs pass or route signals between SSPs, other STPs, and SCPs. An STP is a special application packet switch which operates to pass signaling information.

[0012] The components in the SS7 network are connected together by links. Links between SSPs and STPs can be, for example, A, B, C, D, E or F links. Typically, redundant links are also used for connecting an SSP to its adjacent STPs. Customer premises equipment (CPE), such as a telephone, are connected to an SSP or an end office (EO) switch.

[0013] To initiate a call in an SS7 telecommunications network, a calling party using a telephone connected to an originating EO switch, dials a telephone number of a called party. The telephone number is passed from the telephone to the SSP at the originating EO (referred to as the “ingress EO”) of the calling party's local exchange carrier (LEC). A LEC is commonly referred to as a local telephone company. First, the SSP will process triggers and internal route rules based on satisfaction of certain criteria. Second, the SSP will initiate further signaling messages to another EO or access tandem (AT), if necessary. The signaling information can be passed from the SSP to STPs, which route the signals between the ingress EO and the terminating end office, or egress EO. The egress EO has a port designated by the telephone number of the called party. The call is set up as a direct connection between the EOs through tandem switches if no direct trunking exists or if direct trunking is full. If the call is a long distance call, i.e., between a calling party and a called party located in different local access transport areas (LATAs), then the call is connected through an inter exchange carrier (IXC) switch of any of a number of long distance telephone companies. Such a long distance call is commonly referred to as an inter-LATA call. LECs and IXCs are collectively referred to as the previously mentioned public switched telephone network (PSTN).

[0014] Emergence of competitive LECs (CLECs) was facilitated by passage of the Telecommunications Act of 1996, which authorized competition in the local phone service market. Traditional LECs or RBOCs are now also known as incumbent LECs (ILECs). Thus, CLECs compete with ILECs in providing local exchange services. This competition, however, has still not provided the bandwidth necessary to handle the large volume of voice and data communications. This is due to the limitations of circuit switching technology which limits the bandwidth of the equipment being used by the LECs, and to the high costs of adding additional equipment.

[0015] Since circuit switching dedicates a channel to a call for the duration of the call, a large amount of switching bandwidth is required to handle the high volume of voice calls. This problem is exacerbated by the fact that the LECs must also handle data communications over the same equipment that handle voice communications.

[0016] If the PSTN were converted to a packet-switched network, many of the congestion and limited bandwidth problems would be solved. However, the LECs and IXCs have invested large amounts of capital in building, upgrading and maintaining their circuit switched networks (known as “legacy” networks) and are unable or unwilling to jettison their legacy networks in favor of the newer, more powerful technology of packet switching. Accordingly, a party wanting to build a packet-switched network to provide voice and data communications for customers must build a network that, not only provides the desired functionality, but also is fully compatible with the SS7 and other, e.g., ISDN and MF, switching networks of the legacy systems.

[0017] Currently, internets, intranets, and similar public or private data networks that interconnect computers generally use packet switching technology. Packet switching provides for more efficient use of a communication channel as compared to circuit switching. With packet switching, many different calls (e.g., voice, data, video, fax, Internet, etc.) can share a communication channel rather than the channel being dedicated to a single call. For example, during a voice call, digitized voice information might be transferred between the callers only 50% of the time, with the other 50% being silence. For a data call, information might be transferred between two computers 10% of the time. With a circuit switched connection, the voice call would tie-up a communications channel that may have 50% of its bandwidth being unused. Similarly, with the data call, 90% of the channel's bandwidth may go unused. In contrast, a packet-switched connection would permit the voice call, the data call and possibly other call information to all be sent over the same channel.

[0018] Packet switching breaks a media stream into pieces known as, for example, packets, cells or frames. Each packet is then encoded with address information for delivery to the proper destination and is sent through the network. The packets are received at the destination and the media stream is reassembled into its original form for delivery to the recipient. This process is made possible using an important family of communications protocols, commonly called the Internet Protocol (IP).

[0019] In a packet-switched network, there is no single, unbroken physical connection between sender and receiver. The packets from many different calls share network bandwidth with other transmissions. The packets are sent over many different routes at the same time toward the destination, and then are reassembled at the receiving end. The result is much more efficient use of a telecommunications network than could be achieved with circuit-switching.

[0020] Recognizing the inherent efficiency of packet switched data networks such as the Internet, attention has focused on the transmission of voice information over packet-switched networks. However, such systems are not compatible with the legacy PSTN and therefore are not convenient to use.

[0021] One approach that implements voice communications over an IP network requires that a person dial a special access number to access an IP network. Once the IP network is accessed, the destination or called number can be dialed. This type of call is known as a gateway-type access call.

[0022] Another approach involves a user having a telephone that is dedicated to an IP network. This approach is inflexible since calls can only be made over the IP network without direct access to the PSTN.

[0023] What is needed is a system and method for implementing packet-switched communications for both voice calls and data calls that do not require special access numbers or dedicated phones and permit full integration with the legacy PSTN.

[0024] The present invention is a system and method for communicating both voice and data over a packet-switched network that is adapted to coexist and communicate with a PSTN. The system permits efficient packet switching of voice calls and data calls from a PSTN carrier such as, for example, a LEC, IXC, a customer facility or a direct IP connection on the data network to any other LEC, IXC, customer facility or direct IP connection. For calls from a PSTN carrier, e.g., LEC or IXC, the invention receives signaling from the legacy SS7 signaling network or the ISDN D-channel or from inband signaling trunks. For calls from a customer facility, data channel signaling or inband signaling is received. For calls from a direct IP connection on the data network, signaling messages can travel over the data network. On the call destination side, similar signaling schemes are used depending on whether the called party is on a PSTN carrier, a customer facility or a direct IP connection to the data network.

[0025] The system includes soft switch sites, gateway sites, a data network, a provisioning component a network event component and a network management component. The system of the invention interfaces with customer facilities (e.g., a PBX), carrier facilities (e.g., a PSTN carrier, a LEC (e.g., ILECs and CLECs), an independent telephone company (ITC), an IXC, an intelligent peripheral or an enhanced service provider (ESP)) and legacy signaling networks (e.g., SS7) to handle calls between any combination of on-network and off-network callers.

[0026] The soft switch sites provide the core call processing for the voice network architecture. Each soft switch site can process multiple types of calls including calls originating from or terminating at off-network customer facilities as well as calls originating from or terminating at on-network customer facilities. Each soft switch site receives signaling messages from and sends signaling messages to the signaling network. The signaling messages can include, for example, SS7, integrated services digital network (ISDN) primary rate interface (PRI) and in-band signaling messages. Each soft switch site processes these signaling messages for the purpose of establishing new calls through the data network and tearing down existing calls and in-progress call control functions. Signaling messages can be transmitted between any combination of on-network and off-network callers.

[0027] Signaling messages for a call which either originates off-network or terminates off-network can be carried over the out-of-band signaling network of the PSTN via the soft switch sites. Signaling messages for a call which both originates on-network and terminates on-network can be carried over the data network rather than through the signaling network.

[0028] The gateway sites originate and terminate calls between calling parties and called parties through the data network. The soft switch sites control or manage the gateway sites. In a preferred embodiment, the soft switch sites use a protocol such as, for example, the Internet Protocol Device Control (IPDC) protocol, to manage network access devices in the gateway sites to request the set-up and tear-down of calls. However, other protocols could be used, including, for example, network access server messaging interface (NMI) and the ITU media gateway control protocol (MGCP).

[0029] The gateway sites can also include network access devices to provide access to network resources (i.e., the communication channels or circuits that provide the bandwidth of the data network). The network access devices can be referred to generally as access servers or media gateways. Exemplary access servers or media gateways are trunking gateways (TGs), access gateways (AGs) and network access servers (NASs). The gateway sites provide for transmission of both voice and data traffic through the data network. The gateway sites also provide connectivity to other telecommunications carriers via trunk interfaces to carrier facilities for the handling of voice calls. The trunk interfaces can also be used for the termination of dial-up modem data calls. The gateway sites can also provide connectivity via private lines and dedicated access lines (DALs), such as T1 or ISDN PRI facilities, to customer facilities.

[0030] The data network connects one or more of the soft switch sites to one or more of the gateway sites. The data network routes data packets through routing devices (e.g., routers) to destination sites (e.g., gateway sites and soft switch sites) on the data network. For example, the data network routes internet protocol (IP) packets for transmission of voice and data traffic from a first gateway site to a second gateway site. The data network represents any art-recognized data network including the global Internet, a private intranet or internet, a frame relay network, and an asynchronous transfer mode (ATM) network.

[0031] The network event component collects call events recorded at the soft switch sites. Call event records can be used, for example, for fraud detection and prevention, and billing.

[0032] The provisioning event component receives provisioning requests from upstream operational support services (OSS) systems such as, for example, for order-entry, customer service and customer profile changes. The provisioning component distributes provisioning data to appropriate network elements and maintains data synchronization, consistency, and integrity across multiple soft switch sites.

[0033] The network management component includes a network operations center (NOC) for centralized network management. Each network element (NE) (e.g., soft switch sites, gateway sites, provisioning, and network event components, etc.) generates simple network management protocol (SNMP) events or alerts. The NOC uses the events generated by each network element to determine the health of the network and to perform other network management functions.

[0034] In a preferred embodiment, the invention operates as follows to process, for example, a long distance call (also known as a 1+ call). First, a soft switch site receives an incoming call signaling message from the signaling network. The soft switch site determines the type of call by performing initial digit analysis on the dialed number. Based upon the information in the signaling message, the soft switch site analyzes the initial digit of the dialed number of the call and determines that it is a 1+ call. The soft switch site then queries a customer profile database to retrieve the originating trigger plan associated with the calling customer. The query can be made using, for example, the calling party number provided in the signaling message from the signaling network. This look-up in the customer profile database returns subscription information. For example, the customer profile may indicate that the calling party has subscribed to an account code verification feature that requires entry of an account code before completion of the call. In this case, the soft switch site will instruct the gateway site to collect the account code digits entered by the calling party. Assuming that the gateway site collects the correct number of digits, the soft switch site can use the customer profile to determine how to process the received digits. For account code verification, the soft switch site verifies the validity of the received digits.

[0035] Verification can result in the need to enforce a restriction, such as a class of service (COS) restriction (COSR). In this example, the soft switch site can verify that the account code is valid, but that it requires that an intrastate COSR should be enforced. This means that the call is required to be an intrastate call to be valid. The class of service restriction logic can be performed within the soft switch site using, for example, pre-loaded local access and transport areas (LATAs) and state tables. The soft switch would then allow the call to proceed if the class of service requested matches the authorized class of service. For example, if the LATA and state tables show that the LATA of the originating party and the LATA of the terminating party are in the same state, then the call can be allowed to proceed. The soft switch site then completes customer service processing and prepares to terminate the cal. At this point, the soft switch site has finished executing all customer service logic and has a 10-digit dialed number that must be terminated. To accomplish the termination, the soft switch site determines the terminating gateway. The dialed number (i.e., the number of the called party dialed by the calling party) is used to select a termination on the data network. This termination may be selected based on various performance, availability or cost criteria. The soft switch site then communicates with a second soft switch site associated with the called party to request that the second soft switch site allocate a terminating circuit or trunk group in a gateway site associated with the called party. One of the two soft switch sites can then indicate to the other the connections that the second soft switch site must make to connect the call. The two soft switch sites then instruct the two gateway sites to make the appropriate connections to set up the call. The soft switch sites send messages to the gateway sites through the data network using, for example, IPDC protocol commands. Alternately, a single soft switch can set up both the origination and termination.

[0036] The present invention provides a number of important features and advantages. First, the invention uses application logic to identify and direct incoming data calls straight to a terminating device. This permits data calls to completely bypass the egress end office switch of a LEC. This results in significant cost savings for an entity such as an internet service provider (ISP), ILEC, or CLEC. This decrease in cost results partially from bypass of the egress ILEC end office switch for data traffic.

[0037] A further advantage for ISPs is that they are provided data in the digital form used by data networks (e.g., IP data packets), rather than the digital signals conventionally used by switched voice networks (e.g., PPP signals). Consequently, the ISPs need not perform costly modem conversion processes that would otherwise be necessary. The elimination of many telecommunications processes frees up the functions that ISPs, themselves, would have to perform to provide Internet access.

[0038] Another advantage of the present invention is that voice traffic can be transmitted transparently over a packet-switched data network to a destination on the PSTN.

[0039] Yet another advantage of the invention is that a very large number of modem calls can be passed over a single channel of the data network, including calls carrying media such as voice, bursty data, fax, audio, video, or any other data formats.

[0040] Further features and advantages of the invention, as well as the structure and operation of various embodiments of the invention, are described in detail below with reference to the accompanying figures.

[0175] In the figures, like reference numbers generally indicate identical, functionally similar, and/or structurally similar elements. The figure in which an element first appears is indicated by the leftmost digit(s) in the reference number.

• [0176] I. High Level Description

[0177] A. Structural Description

• • [0178] 1. Soft Switch Sites
  • [0179] 2. Gateway Sites
  • [0180] 3. Data Network
  • [0181] 4. Signaling Network
  • [0182] 5. Network Event Component
  • [0183] 6. Provisioning Component
  • [0184] 7. Network Management Component

[0185] B. Operational Description

• [0186] II. Intermediate Level Description

[0187] A. Structural Description

• • [0188] 1. Soft Switch Site
    • [0189] a. Soft Switch
    • [0190] b. SS7 Gateway
    • [0191] c. Signal Transfer Points (STPs)
    • [0192] d. Services Control Points (SCPs)
    • [0193] e. Configuration Server (CS) or Configuration Database (CDB)
    • [0194] f. Route Server
    • [0195] g. Regional Network Event Collection Point (RNECP)
  • [0196] 2. Gateway Site
    • [0197] a. Trunking Gateway (TG)
    • [0198] b. Access Gateway (AG)
    • [0199] c. Network Access Server (NAS)
    • [0200] d. Digital Cross-Connect System (DACS)
    • [0201] e. Announcement Server (ANS)
  • [0202] 3. Data Network
    • [0203] a. Routers
    • [0204] b. Local Area Networks (LANs) and Wide Area Networks (WANs)
    • [0205] c. Network Protocols
  • [0206] 4. Signaling Network
    • [0207] a. Signal Transfer Points (STPs)
    • [0208] b. Service Switching Points (SSPs)
    • [0209] c. Services Control Points (SCPs)
  • [0210] 5. Provisioning Component and Network Event Component
    • [0211] a. Data Distributor
  • [0212] 6. Provisioning Component and Network Event Component
    • [0213] a. Master Network Event Database
  • [0214] 7. Network management component

[0215] B. Operational Description

• [0216] III. Specific Implementation Example Embodiments

[0217] A. Structural Description

• • [0218] 1. Soft Switch Site
    • [0219] a. Soft Switch
      • [0220] (1) Soft Switch Interfaces
    • [0221] b. SS7 Gateway
      • [0222] (1) SS7 Gateway Example Embodiment
      • [0223] (2) SS7 Gateway-to-Soft Switch Interface
    • [0224] c. Signal Transfer Points (STPs)
      • [0225] (1) STP Example Embodiment
        • [0226] (a) Global Title Translation
        • [0227] (b) Gateway Screening Software
        • [0228] (c) Local Number Portability (LNP)
        • [0229] (d) STP to LAN Interface
        • [0230] (e) ANSI to ITU Gateway
    • [0231] d. Services Control Points (SCPs)
      • [0232] (1) Additional Services Calls
      • [0233] (2) Project Account Codes
      • [0234] (3) Basic Toll-Free
    • [0235] e. Configuration Server (CS) or Configuration Database (CDB)
    • [0236] f. Route Server
      • [0237] (1) Route Server Routing Logic
      • [0238] (2) Route Server Circuit Management
    • [0239] g. Regional Network Event Collection Point (RNECP)
      • [0240] (1) Example Mandatory Event Blocks EBs
      • [0241] (2) Augmenting Event Blocks EBs
    • [0242] h. Software Object Oriented Programming (OOPs) Class Definitions
      • [0243] (1) Introduction to Object Oriented Programming (OOP)
      • [0244] (2) Software Objects in an OOP Environment
      • [0245] (3) Class Definitions
        • [0246] (a) Soft Switch Class
        • [0247] (b) Call Context Class
        • [0248] (c) Signaling Message Class
        • [0249] (d) SS7 Gateway Class
        • [0250] (e) IPDC Message Class
        • [0251] (f) Call Event Identifier Class
        • [0252] (g) Configuration Proxy Class
        • [0253] (h) Route Server Class
        • [0254] (i) Route Objects Class
        • [0255] (j) Pool Class
        • [0256] (k) Circuit Pool Class
  • [0257] 2. Gateway Site
    • [0258] a. Trunking Gateway (TG)
      • [0259] (1) Trunking Gateway Interfaces
    • [0260] b. Access Gateway (AG)
      • [0261] (1) Access Gateway Interfaces
    • [0262] c. Network Access Server (NAS)
      • [0263] (1) Network Access Server Interfaces
    • [0264] d. Digital Cross-Connect System (DACS)
    • [0265] e. Announcement Server (ANS)
  • [0266] 3. Data Network
    • [0267] a. Routers
    • [0268] b. Local Area Networks (LANs) and Wide Area Networks (WANs)
    • [0269] c. Network Protocols
      • [0270] (1) Transmission Control Protocol/Internet Protocol (TCP/IP)
      • [0271] (2) Internet Protocol (IP)v4 and IPv6
      • [0272] (3) Resource Reservation Protocol (RSVP)
      • [0273] (4) Real-time Transport Protocol (RTP)
      • [0274] (5) IP Multi-Casting Protocols
    • [0275] d. Virtual Private Networks (VPNs)
      • [0276] (1) VPN Protocols
        • [0277] (a) Point-to-Point Tunneling Protocol (PPTP)
        • [0278] (b) Layer 2 Forwarding (L2F) Protocol
        • [0279] (c) Layer 2 Tunneling Protocol (L2TP)
    • [0280] e. Exemplary Data Networks
      • [0281] (1) Asynchronous Transfer Mode (ATM)
      • [0282] (2) Frame Relay
      • [0283] (3) Internet Protocol (IP)
  • [0284] 4. Signaling Network
    • [0285] a. Signal Transfer Points (STPs)
    • [0286] b. Service Switching Points (SSPs)
    • [0287] c. Services Control Points (SCPs)
  • [0288] 5. Provisioning Component and Network Event Component
    • [0289] a. Data Distributor
      • [0290] (1) Data Distributor Interfaces
  • [0291] 6. Provisioning Component and Network Event Component
    • [0292] a. Master Network Event Database
      • [0293] (1) MNEDB Interfaces
      • [0294] (2) Event Block Definitions
        • [0295] (a) Example Mandatory Event Blocks (EBs) Definitions
        • [0296] (b) Example Augmenting Event Block (EBs) Definitions
      • [0297] (3) Example Element Definitions
      • [0298] (4) Element Definitions
  • [0299] 7. Network management component
    • [0300] a. Network operations center (NOC)
    • [0301] b. Simple Network Management Protocol (SNMP)
    • [0302] c. Network Outage Recovery Scenarios
      • [0303] (1) Complete Gateway Site Outage
      • [0304] (2) Soft Switch Fail-Over
      • [0305] (3) Complete Soft Switch Site Outage Scenario
  • [0306] 8. Internet Protocol Device Control (IPDC) Protocol
    • [0307] a. IPDC Base Protocol
    • [0308] b. IPDC Control Protocol
    • [0309] c. IPDC Control Message Codes
    • [0310] d. A Detailed View of the IPDC Protocol Control Messages
      • [0311] (1) Startup Messages
      • [0312] (2) Protocol Error Messages
      • [0313] (3) System Configuration Messages
      • [0314] (4) Telephone Company Interface Configuration Messages
      • [0315] (5) Soft Switch Configuration Messages
      • [0316] (6) Maintenance-Status Messages
      • [0317] (7) Continuity Test Messages
      • [0318] (8) Keepalive Test Messages
      • [0319] (9) LAN Test Messages
      • [0320] (10) Tone Function Messages
      • [0321] (11) Example Source Port Types
      • [0322] (12) Example Internal Resource Types
      • [0323] (13) Example Destination Port Types
      • [0324] (14) Call Control Messages
      • [0325] (15) Example Port Definitions
      • [0326] (16) Call Clearing Messages
      • [0327] (17) Event Notification Messages
      • [0328] (18) Tunneled Signaling Messages
    • [0329] e. Control Message Parameters
    • [0330] f. A Detailed View of the Flow of Control Messages
      • [0331] (1) Startup Flow
      • [0332] (2) Module Status Notification Flow
      • [0333] (3) Line Status Notification Flow
      • [0334] (4) Blocking of Channels Flow
      • [0335] (5) Unblocking of Channels Flow
      • [0336] (6) Keepalive Test Flow
      • [0337] (7) Reset Request Flow
    • [0338] g. Call Flows
      • [0339] (1) Data Services
        • [0340] (a) Inbound Data Call via SS7 Signaling Flow
        • [0341] (b) Inbound Data Call via Access Server Signaling Flow
        • [0342] (c) Inbound Data Call via SS7 Signaling (with call-back)
        • [0343] (d) Inbound Data Call (with loopback continuity testing) Flow
        • [0344] (e) Outbound Data Call Flow via SS7 Signaling
        • [0345] (f) Outbound Data Call Flow via Access Server Signaling
        • [0346] (g) Outbound Data Call Flow Initiated from the Access Server with continuity testing
      • [0347] (2) TDM Switching Setup Connection Flow
        • [0348] (a) Basic TDM Interaction Sequence
        • [0349] (b) Routing of calls to Appropriate Access Server using TDM connections Flow
      • [0350] (3) Voice Services
        • [0351] (a) Voice over Packet Services Call Flow (Inbound SS7 signaling, Outbound access server signaling, Soft Switch managed RTP ports)
        • [0352] (b) Voice over Packet Call Flow (Inbound access server signaling, Outbound access server signaling, Soft switch managed RTP ports)
        • [0353] (c) Voice over Packet Call Flow (Inbound SS7 signaling, outbound SS7 signaling, IP network with access server managed RTP ports)
        • [0354] (d) Unattended Call Transfers Call Flow
        • [0355] (e) Attended Call Transfer Call Flow
        • [0356] (f) Call termination with a message announcement Call Flow
        • [0357] (g) Wiretap

[0358] B. Operational Description

• • [0359] 1. Voice Call originating and terminating via SS7 signaling on a Trunking Gateway
    • [0360] a. Voice Call on a TG Sequence Diagrams of Component Intercommunication
  • [0361] 2. Data Call originating on an SS7 trunk on a Trunking Gateway
  • [0362] 3. Voice Call originating on an SS7 trunk on a Trunking Gateway and terminating via access server signaling on an Access Gateway
  • [0363] 4. Voice Call originating on an SS7 trunk on a Trunking Gateway and terminating on an Announcement Server
  • [0364] 5. Voice Call originating on an SS7 trunk on a Network Access Server and terminating on a Trunking Gateway via SS7 signaling
    • [0365] a. Voice Call on a NAS Sequence Diagrams of Component Intercommunication
  • [0366] 6 Voice Call originating on an SS7 trunk on a NAS and terminating via Access Server Signaling on an Access Gateway
  • [0367] 7. Data Call originating on an SS7 trunk and terminating on a NAS
    • [0368] a. Data Call on a NAS Sequence Diagrams of Component intercommunication
  • [0369] 8. Data Call on NAS with Callback outbound reorigination
  • [0370] 9. Voice Call originating on Access Server dedicated line on an Access Gateway and terminating on an Access Server dedicated line on an Access Gateway
  • [0371] 10. Voice Call originating on Access Server signaled private line on an Access Gateway and terminating on SS7 signaled trunks on a Trunking Gateway
  • [0372] 11. Data Call on an Access Gateway
  • [0373] 12. Outbound Data Call from a NAS via Access Server signaling from an Access Gateway
  • [0374] 13. Voice Services
    • [0375] a. Private Voice Network (PVN) Service
    • [0376] b. 1+ Long Distance Service
      • [0377] (1) Project Account Codes (PAC)
        • [0378] (a) PAC Variations
      • [0379] (2) Class of Service Restrictions (COSR)
      • [0380] (3) Origination and Termination
      • [0381] (4) Call Rating
      • [0382] (5) Multiple Service T-1
      • [0383] (6) Monthly Recurring Charges (MRCs)
      • [0384] (7) PVN Private Dialing Plan
      • [0385] (8) Three-Way Conferencing
      • [0386] (9) Network Hold with Message Delivery
    • [0387] c. 8XX Toll Free Services
      • [0388] (1) Enhanced Routing Features
      • [0389] (2) Info-Digit Blocking
      • [0390] (3) Toll-Free Number Portability (TFNP)
      • [0391] (4) Multiple-Server T-1
      • [0392] (5) Call Rating
      • [0393] (6) Project Accounting Codes
      • [0394] (7) Toll-Free Directory Listings
      • [0395] (8) Menu Routing
      • [0396] (9) Network ACD
      • [0397] (10) Network Transfer (TBX)
      • [0398] (11) Quota Routing
      • [0399] (12) Toll-Free Valet (Call Park)
    • [0400] d. Operator Services
      • [0401] (1) Domestic Operator Services
        • [0402] (a) Operator Services Features
      • [0403] (2) International Operator Services
    • [0404] e. Calling Card Services
      • [0405] (1) Calling Card Features
      • [0406] (2) Call Rating
    • [0407] f. One-Number Services
      • [0408] (1) One Number Features
    • [0409] g. Debit Card/Credit Card Call Services
    • [0410] h. Local Services
      • [0411] (1) Local Voice/Dial Tone (LV/DT)
      • [0412] (2) Call Handling Features
        • [0413] (a) Line Hunting
        • [0414] (b) Call Forward Busy
        • [0415] (c) Call Forwarding Don't Answer
        • [0416] (d) Call Forward Variable
        • [0417] (e) Call Hold
        • [0418] (f) Three-Way Calling
        • [0419] (g) Call Transfer
        • [0420] (h) Call Waiting/Cancel Call Waiting
        • [0421] (i) Extension or Station-to-Station Calling
        • [0422] (j) Direct Connect Hotline/Ring Down Line
        • [0423] (k) Message Waiting Indicator
        • [0424] (l) Distinctive Ringing
        • [0425] (m) Six-Way Conference Calling
        • [0426] (n) Speed Calling
        • [0427] (o) Selective Call Rejection
        • [0428] (p) Remote Activation of Call Forward Variable
      • [0429] (3) Enhanced Services
        • [0430] (a) Remote Call Forward (RCF)
        • [0431] (b) Voice Messaging Services
        • [0432] (c) Integrated Voice Messaging
        • [0433] (d) Stand-alone Voice Messaging
      • [0434] (4) Class Services
      • [0435] (5) Class of Service Restrictions
    • [0436] (b) Local Voice/Local Calling (LV/LC)
  • [0437] i. Conferencing Services
    • [0438] (1) Audio Conferencing
      • [0439] (a) Audio conferencing features
    • [0440] (2) Video Conferencing
  • [0441] 14. Data Services
    • [0442] a. Internet Hosting
    • [0443] b. Managed Modem Services
    • [0444] c. Collocation Services
    • [0445] d. IP network Services
    • [0446] e. Legacy Protocol Services—Systems Network Architecture (SNA)
    • [0447] f. Permanent Virtual Circuits

[0448] 15. Additional Products and Services

• [0449] IV. Definitions
• [0450] V. Conclusion

[0451] This section provides a high-level description of the voice over IP network architecture according to the present invention. In particular, a structural implementation of the voice over IP (VOIP) network architecture is described at a high-level. Also, a functional implementation for this structure is described at a high-level. This structural implementation is described herein for illustrative purposes, and is not limiting. In particular, the process described in this section can be achieved using any number of structural implementations, one of which is described in this section. The details of such structural implementations will be apparent to persons skilled in the relevant arts based on the teachings contained herein.

[0452] A. Structural Description

[0453] FIG. 1 is a block diagram 100 illustrating the components of the VOIP architecture at a high-level. FIG. 1 includes soft switch sites 104, 106, gateway sites 108, 110, data network 112, signaling network 114, network event component 116, provisioning component 117 and network management component 118.

[0454] Included in FIG. 1 are calling parties 102, 122 and called parties 120, 124. Calling parties 102, 122 are homed to gateway site 108. Calling parties 102, 122 are homed to gateway site 108. Called parties 120, 124 are homed to gateway site 110. Calling party 102 can be connected to gateway site 108 via trunks from carrier facility 126 to gateway site 108. Similarly, called party 120 can be connected to gateway site 110 via trunks from carrier facility 130 to gateway site 110. Calling party 122 can be connected to gateway site 108 via a private line or dedicated access line (DAL) from customer facility 128 to gateway site 108. Similarly, called party 124 can be connected to gateway site 110 via a private line or a DAL from customer facility 132 to gateway site 110.

[0455] Calling party 102 and called party 120 are off-network, meaning that they are connected to gateway sites 108, 110 via the Public Switched Telephone Network (PSTN) facilities. Calling party 122 and called party 124 are on-network, meaning that connect to gateway sites 108, 110 as direct customers.

[0456] Soft switch sites 104, 106 provide the core call processing for the voice network architecture. Soft switch sites 104, 106 can process multiple types of calls. First, soft switch sites 104, 106 can process calls originating from or terminating at on-network customer facilities 128, 132. Second, soft switch sites 104, 106 can process calls originating from or terminating at off-network customer facilities 126, 130.

[0457] Soft switch sites 104, 106 receive signaling messages from and send signaling messages to signaling network 114. For example, these signaling messages can include SS7, primary rate interface (PRI) and in-band signaling messages. Soft switch sites 104, 106 process these signaling messages for the purpose of establishing new calls from calling parties 102, 122 through data network 112 to called parties 120, 124. Soft switch sites 104, 106 also process these signaling messages for the purpose of tearing down existing calls established between calling parties 102, 122 and called parties 120, 124 (through data network 112).

[0458] Calls can be transmitted between any combination of on-network and off-network callers.

[0459] In one embodiment, signaling messages for a call which either originates from an off-network calling party 102, or terminates to an off-network called party 120, can be carried over out-of-band signaling network 114 from the PSTN to soft switches 104, 106.

[0460] In another embodiment, signaling messages for a call which either originates from an on-network calling party 122, or terminates to on-network called party 124, can be carried in-band over data network 112 or over a separate data network to soft switch sites 104, 106, rather than through signaling network 114.

[0461] Soft switch sites 104, 106 can be collocated or geographically diverse. Soft switch sites 104, 106 can also be connected by redundant connections to data network 112 to enable communication between soft switches 104, 106.

[0462] Soft switch sites 104, 106 use other voice network components to assist with the processing of calls. For example, gateway sites 108, 110 provide the means to originate and terminate calls on the PSTN. In a preferred embodiment, soft switch sites 104, 106 use the Internet Protocol Device Control (IPDC) protocol to control network access devices known as media gateways in gateway sites 108, 110, and to request, for example, the set-up and tear-down of calls. The IPDC protocol is described below with reference to Tables 144-185. Alternatively, any protocol understood by those skilled in the art can be used to control gateway sites 108, 110. One example of an alternative protocol is the Network Access Server (NAS) Messaging Interface (NMI) Protocol, discussed in U.S. patent application entitled “System and Method for Bypassing Data from Egress Facilities”, filed concurrently herewith, Ser. No. 09/196,756, the contents of which are incorporated herein by reference in their entirety. Another example of a protocol is the Media Gateway Control Protocol (MGCP) from the Internet Engineering Task Force (IETF).

[0463] Soft switch sites 104, 106 can include other network components such as a soft switch, which more recently can also be known as a media gateway controller, or other network devices.

[0464] Gateway sites 108, 110 provide the means to originate and terminate calls between calling parties 102, 122 and called parties 120, 124 through data network 112. For example, calling party 122 can originate a call terminated to off-network called party 120, which is homed to gateway site 110 via carrier facility 130.

[0465] Gateway sites 108, 110 can include network access devices to provide access to network resources. An example of a network access device is an access server which is more recently commonly known as a media gateway. These devices can include trunking gateways, access gateways and network access servers. Gateway sites 108, 110 provide for transmission of, for example, both voice and data traffic through data network 112.

[0466] Gateway sites 108, 110 are controlled or managed by one or more soft switch sites 104, 106. As noted, soft switch sites 104, 106 can communicate with gateway sites 108, 110 via the IPDC, NMI, MGCP, or alternative protocols.

[0467] Gateway sites 108, 110 can provide trunk interfaces to other telecommunication carriers via carrier facilities 126, 130 for the handling of voice calls. The trunk interfaces can also be used for the termination of dial-up modem data calls. Gateway sites 108, 110 can also provide private lines and dedicated access lines, such as T1 or ISDN PRI facilities, to customer facilities 128, 132. Examples of customer facilities 128, 132 are customer premises equipment (CPE) such as, for example, a private branch exchange (PBX).

[0468] Gateway sites 108, 110 can be collocated or geographically diverse from one another or from other network elements (e.g. soft switch sites 104, 106). Gateway sites 108, 110 can also be connected by redundant connections to data network 112 to enable communication with and management by soft switches 104, 106.

[0469] Data network 112 connects one or more soft switch sites 104, 106 to one or more gateway sites 108, 110. Data Network 112 can provide for routing of data through routing devices to destination sites on data network 112. For example, data network 112 can provide for routing of internet protocol (IP) packets for transmission of voice and data traffic from gateway site 108 to gateway site 110. Data Network 112 represents any art-recognized data network. One well-known data network is the global Internet. Other examples include a private intranet, a packet-switched network, a frame relay network, and an asynchronous transfer mode (ATM) network.

[0470] Signaling network 114 is an out-of-band signaling network providing for transmission of signaling messages between the PSTN and soft switch sites 104, 106. For example, signaling network 114 can use Common Channel Interoffice Signaling (CCIS), which is a network architecture for out-of-band signaling. A popular version of CCIS signaling is Signaling System 7 (SS7). SS7 is an internationally recognized system optimized for use in digital telecommunications networks.

[0471] Network event component 116 provides for collection of call events recorded at soft switch sites 104, 106. Call event records can be used, for example, for fraud detection and prevention, traffic reporting and billing.

[0472] Provisioning component 117 provides several functions. First, provisioning component 117 receives provisioning requests from upstream operational support services (OSS) systems, for such items as order-entry, customer service, and customer profile changes. Second, provisioning component 117 distributes provisioning data to appropriate network elements. Third provisioning component 117 maintains data synchronization, consistency, and integrity across multiple soft switch sites 104, 106.

[0473] Network management component 118 can include a network operations center (NOC) for centralized network management. Each network element (NE) of block diagram 100 can generate simple network management protocol (SNMP) events or alerts. The NOC uses the events generated by a NE to determine the health of the network, and to perform other network management functions.

[0474] B. Operational Description

[0475] The following operational flows describe an exemplary high level call scenario for soft switch sites 104, 106 and is intended to demonstrate at a high architectural level how soft switch sites 104, 106 process calls. The operational flow of the present invention is not to be viewed as limited to this exemplary illustration.

[0476] As an illustration, FIG. 22A depicts a simple operational call flow chart describing how soft switch sites 104, 106 can process a long distance call, also known as a 1+ call. The operational call flow of FIG. 22A begins with step 2202, in which a soft switch site receives an incoming signaling message. The call starts by soft switch site 104 receiving an incoming signaling message from carrier facility 126 via signaling network 114, indicating an incoming call from calling party 102.

[0477] In step 2204, the soft switch site determines the type of call by performing initial digit analysis. Based upon the information in the signaling message, the soft switch site 104 analyzes the initial digit of the dialed number of the call and determines that it is a 1+ call.

[0478] In step 2222, soft switch site 104 can select a route termination based on the dialed number (i.e., the number of called party 120 dialed by calling party 102) using least cost routing. This route termination can involve termination off data network 112 or off onto another data network. Soft switch site 104 can then communicate with soft switch site 106 to allocate a terminating circuit in gateway site 110 for this call.

[0479] In step 2224, soft switch site 104 can indicate connections to be made to complete the call. Soft switch site 104 or soft switch site 106 can return a termination that indicates the connections that must be made to connect the call.

[0480] In step 2226, soft switch sites 104, 106 instruct the gateway sites to make connections to set up the call. Soft switch sites 104, 106 can send messages through data network 112 (e.g. using IPDC protocol commands) to gateway sites 108, 110, to instruct the gateway sites to make the necessary connections for setting up the call origination from calling party 102, the call termination to called party 120, and the connection between origination and termination.

[0481] In step 2228, soft switch sites 104, 106 generate and send network events to a repository. Soft switch sites 104, 106 can generate and send network events to network event component 116 that are used, for example, in detecting and preventing fraud, and in performing billing.

[0482] In step 2230, network management component 118 monitors the telecommunications network 100. All network elements create network management events such as SNMP protocol alerts or events. Network management component 118 can monitor SNMP events to enable management of network resources.

[0483] FIG. 22B details a more complex operational call flow describing how soft switch sites 104, 106 process a long distance call. FIG. 22B inserts steps 2206, 2208 and 2220 between steps 2204 and 2222 of FIG. 22A.

[0484] The operational call flow of FIG. 22B begins with step 2202, in which a soft switch site receives an incoming signaling message. The call starts by soft switch site 104 receiving an incoming signaling message from carrier facility 126 via signaling network 114, indicating an incoming call from calling party 102.

[0485] In step 2204, the soft switch site determines the-type of call by performing initial digit analysis. Based upon the information in the signaling message, the soft switch site 104 analyzes the initial digit of the dialed number of the call and determines that it is a 1+ call.

[0486] In step 2206, the soft switch site queries a customer profile database to retrieve the originating trigger plan associated with the calling customer. With a 1+ type of call, the logic within the soft switch knows to query the customer profile database within soft switch site 104 to retrieve the originating trigger plan for the calling party. The step 2206 query can be made using the calling party number. The customer profile lookup is performed using as the lookup key, the originating number, i.e., the number of calling party 102, provided in the signaling message from signaling network 114.

[0487] In step 2208, the lookup returns subscription information. For example, the customer profile can require entry of an account code. In this example, the customer profile lookup can return an indication that the customer, i.e., calling party 102, has subscribed to an account code verification feature. A class of service restriction can also be enforced, but this will not be known until account code verification identifies an associated account code.

[0488] In step 2220, soft switch site 104 completes customer service processing and prepares to terminate the call. At this point, soft switch site 104 has finished executing all customer service logic and has a 10-digit dialed number that must be terminated.

[0489] In step 2222, soft switch site 104 can select a route termination based on the dialed number (i.e., the number of called party 120 dialed by calling party 102) using least cost routing. This route termination can involve termination off data network 112 or off onto another data network. Soft switch site 104 can then communicate with soft switch site 106 to allocate a terminating circuit in gateway site 110 for this call.

[0490] In step 2224, soft switch site 104 can indicate connections to be made to complete the call. Soft switch site 104 or soft switch site 106 can return a termination that indicates the connections that must be made to connect the call.

[0491] In step 2226, soft switch sites 104, 106 instruct the gateway sites to make connections to set up the call. Soft switch sites 104, 106 can send messages through data network 112 (e.g. using IPDC protocol commands) to gateway sites 108, 110, to instruct the gateway sites to make the necessary connections for setting up the call origination from calling party 102, the call termination to called party 120, and the connection between origination and termination.

[0492] In step 2228, soft switch sites 104, 106 generate and send network events to a repository. Soft switch sites 104, 106 can generate and send network events to network event component 116 that are used, for example, in detecting and preventing fraud, and in performing billing.

[0493] In step 2230, network management component 118 monitors the telecommunications network 100. All network elements create network management events such as SNMP protocol alerts or events. Network management component 118 can monitor SNMP events to enable management of network resources.

[0494] FIG. 22C details an even more complex operational call flow describing how soft switch sites 104, 106 can be used to process a long distance call using project account codes and class of service restrictions. FIG. 22C inserts steps 2210 through 2218 between steps 2208 and 2220 of FIG. 22B.

[0495] The operational call flow of FIG. 22C begins with step 2202, in which a soft switch site receives an incoming signaling message. The call starts by soft switch site 104 receiving an incoming signaling message from carrier facility 126 via signaling network 114, indicating an incoming call from calling party 102.

[0496] In step 2204, the soft switch site determines the type of call by performing initial digit analysis. Based upon the information in the signaling message, the soft switch site 104 analyzes the initial digit of the dialed number of the call and determines that it is a 1+ call.

[0497] In step 2206, the soft switch site queries a customer profile database to retrieve the originating trigger plan associated with the calling customer. With a 1+ type of call, the logic within the soft switch knows to query the customer profile database within soft switch site 104 to retrieve the originating trigger plan for the calling party. The step 2206 query can be made using the calling party number. The customer profile lookup is performed using as the lookup key, the originating number, i.e., the number of calling party 102, provided in the signaling message from signaling network 114.

[0498] In step 2208, the lookup returns subscription information. For example, the customer profile can require entry of an account code. In this example, the customer profile lookup can return an indication that the customer, i.e., calling party 102, has subscribed to an account code verification feature. A class of service restriction can also be enforced, but this will not be known until account code verification identifies an associated account code.

[0499] In step 2210, soft switch site 104 instructs gateway site 108 to collect account codes. Using the information in the customer profile, soft switch site 104 can use the IPDC protocol to instruct gateway site 108 to collect a specified number of digits from calling party 102.

[0500] In step 2212, soft switch site 104 determines how to process received digits. Assuming gateway site 108 collects the correct number of digits, soft switch site 104 can use the customer profile to determine how to process the received digits. For account code verification, the customer profile can specify whether the account code needs to be validated.

[0501] In step 2214, soft switch site 104 verifies the validity of the received digits. If the account code settings in the customer profile specify that the account code must be verified and forced to meet certain criteria, soft switch site 104 performs two functions. Because “verify” was specified, soft switch site 104 queries a database to verify that the collected digits meet such criteria, i.e., that the collected digits are valid. Because “forced” was specified, soft switch site 104 also forces the calling customer to re-enter the digits if the digits were not valid.

[0502] In step 2216, verification can result in the need to enforce a restriction, such as a class of service (COS) restriction (COSR). In this example, soft switch site 104 can verify that the code is valid, but that it requires, for example, that an intrastate COSR should be enforced. This means that the call is required to be an intrastate call to be valid. The class of service restriction logic can be performed within soft switch site 104 using, for example, pre-loaded local access and transport areas (LATAs) and state tables.

[0503] If project account codes (PACs) are not used, class of service (COS) restrictions can be applied based on originating ANI or ingress trunk group.

[0504] In step 2218, soft switch 104 allows the call to proceed if the class of service requested is permitted. For example, if the LATA and state tables show that the LATAs of originating party (i.e., calling party 102) and terminating party (i.e. called party 120), must be, and are, in the same state, then the call can be allowed to proceed.

[0505] In step 2220, soft switch site 104 completes customer service processing and prepares to terminate the call. At this point, soft switch site 104 has finished executing all customer service logic and has a 10-digit dialed number that must be terminated.

[0506] In step 2222, soft switch site 104 can select a route termination based on the dialed number (i.e., the number of called party 120 dialed by calling party 102) using least cost routing. This route termination can involve termination off data network 112 or off onto another data network. Soft switch site 104 can then communicate with soft switch site 106 to allocate a terminating circuit in gateway site 110 for this call.

[0507] In step 2224, soft switch site 104 can indicate connections to be made to complete the call. Soft switch site 104 or soft switch site 106 can return a termination that indicates the connections that must be made to connect the call.

[0508] In step 2226, soft switch sites 104, 106 instruct the gateway sites to make connections to set up the call. Soft switch sites 104, 106 can send messages through data network 112 (e.g. using IPDC protocol commands) to gateway sites 108, 110, to instruct the gateway sites to make the necessary connections for setting up the call origination from calling party 102, the call termination to called party 120, and the connection between origination and termination.

[0509] In step 2228, soft switch sites 104, 106 generate and send network events to a repository. Soft switch sites 104, 106 can generate and send network events to network event component 116 that are used, for example, in detecting and preventing fraud, and in performing billing.

[0510] In step 2230, network management component 118 monitors the telecommunications network 100. All network elements create network management events such as SNMP protocol alerts or events. Network management component 118 can monitor SNMP events to enable management of network resources.

[0511] The intermediate level description and specific implementation example embodiments sections, below, will describe additional details of operation of the invention. For example, how soft-switch site 104 performs initial digit analysis to identify the type of call and how to process the call will be discussed further. The sections also provide details regarding how soft switch sites 104, 106 interact with the other components of the voice network architecture.

[0512] This section provides an intermediate level description of the VOIP network architecture according to the present invention. A structural implementation of the VOIP network architecture is described at an intermediate level. Also, a functional implementation for this structure is described at an intermediate level. This structural implementation is described herein for illustrative purposes, and is not limiting. In particular, the process described in this section can be achieved using any number of structural implementations, one of which is described in this section. The details of such structural implementations will be apparent to persons skilled in the relevant arts based on the teachings contained herein.

[0513] A. Structural Description

[0514] FIG. 2A is a block diagram further illustrating the components of VOIP architecture 100 at an intermediate level of detail. FIG. 2A depicts telecommunications system 200. Telecommunications system 200 includes soft switch site 104, gateway sites 108, 110, data network 112, signaling network 114, network event component 116, provisioning component 117 and network management component 118. Included in FIG. 2A are calling parties 102, 122 and called parties 120, 124.

[0515] Soft switch site 104 includes soft switch 204, SS7 gateways 208, 210, service control point (SCP) 214, configuration server/configuration database (CDB) 206, route server 212, signal transfer points (STPs) 250, 252, and regional network event collection point (RNECP) 224. Table 1 below describes the functions of these network elements in detail.

[0516]

TABLE 1
Soft switch component	Description
soft switch (SS)	Soft switches are call control components
	responsible for processing of signaling
	messages, execution of call logic and control
	of gateway site access devices.
SS7 gateways (SS7 GW)	SS7 gateways provide an interface between the
	SS7 signaling network and the soft switch.
service switching	Service switching points are the portions of
points (SSP)	backbone switches providing SS7 functions.
	For example, any switch in the PSTN is an SSP
	if it provides SS7 functions. A soft switch is an
	SSP.
signal transfer	Signal transfer points route signaling messages
point (STP)	from originating service switching points
	(SSPs) to destination SSPs.
service control	Service control points provide number
point (SCP)	translations for toll free services and validation
	of project account codes for PAC services.
configuration	Configuration servers are servers managing
server/configuration	customer profiles, voice network topologies
database (CDB)	and configuration data. The configuration
	database is used for storage and retrieval of
	such data.
route server (RS)	Route servers are responsible for selection of
	least cost routes through the network and
	allocation of network ports.
regional network	Route servers are responsible for selection of
event collection	least cost routes through the network and
point (RNECP)	allocation of network ports. regional network
	event collection points are points in the
	network that collect call event data.

[0517] Gateway site 108 includes trunking gateway (TG) 232, access gateway (AG) 238, network access server (NAS) 228, digital cross-connect system (DACS) 242 and announcement server (ANS) 246. TG 232, AG 238, and NAS 228 are collectively known as access server 254. Similarly, gateway site 110 includes TG 234, AG 240, NAS 230, DACS 244 and ANS 248. TG 234, AG 240, and NAS 230 are collectively known as access server 256. Gateway sites 108, 110 provide trunk, private line and dedicated access line connectivity to the PSTN. Table 2 below describes the functions of these network elements in detail.

[0518]

TABLE 2
Gateway site component	Description
trunking gateway (TG)	A trunking gateway provides full-duplex PSTN
	to IP conversion for co-carrier and feature
	group D (FG-D) trunks.
access gateway (AG)	An access gateway provides full-duplex PSTN
	to IP conversion for ISDN-PRI and T1 digital
	dedicated access lines (DALs).
network access	A network access server provides modem
server (NAS)	access to an IP network.
digital access and cross-	A digital access and cross-connect
connect system (DACS)	system is a digital switching
	system used for the routing and switching of
	T-1 lines and DS-0 circuits of lines, among
	multiple T-1 ports.
announcement	An announcement server provides a network
server (ANS)	with PSTN terminating announcements.

[0519] Data network 112 provides the network bandwidth over which calls can be connected through the telecommunications system. Data network 112 can be, for example, a packet switched data network including network routers for routing traffic through the network.

[0520] Signaling network 114 includes signal transfer points (STPs) 216, 218 and signaling control points (SCPs) associated with each network node. Table 3 below describes the functions of these network elements in detail.

[0521]

TABLE 3
Signaling
network
component	Description
signal transfer	Signal transfer points route signaling messages from
points (STPs)	originating service switching points (SSPs) to
	destination SSPs.
service control	Service control point provide number translations
point (SCP)	for Toll Free services and validation of project account
	codes (PAC) for PAC services.
service switching	Service switching points are the portions of backbone
point (SSPs)	switches providing SS7 functions. For example, any
	switch in the PSTN is an SSP if it provides SS7
	functions. A soft switch is an SSP.

[0522] Network management component 118 includes the means to manage a network. Network management component 118 gathers events and alarms related to network events. For example, event logs can be centrally managed from a network operations center (NOC). Alerts and events can be communicated to the NOC via the simple network management protocol (SNMP)). Table 4 below describes the functions of these network elements in detail.

[0523]

TABLE 4
Network
management
component	Description
network operations	Network operations center is a centralized
center (NOC)	location for gathering network management
	events and for managing various network
	elements via the SNMP protocol.
simple network	Simple network management protocol provides
management protocol	site filtering of element alarms and messages
(SNMP)	before forwarding them to the NOC.

[0524] Network event component 116 includes master network event database (MNEDB) 226. Table 5A below describes the functions of this network element in detail.

[0525]

TABLE 5A
Network
event
component	Description
master network	Master network event database is a centralized
event database	server/database that collects call event records
(MNEDB)	from regional network event collection points (RNECPs).
	It serves as a depository for the event records.

[0526] Provisioning component 117 includes data distributor (DD) 222. Table 5B below describes the functions of this network element in detail.

[0527]

TABLE 5B
Provisioning component	Description
data distributor (DD)	The data distributor distributes service requests
	and data from upstream Operational Support
	Systems (OSS) to network elements. It
	maintains synchronization of redundant
	network resources.

[0528] B. Operational Description

[0529] The following operational flow describes an exemplary intermediate level call scenario intended to demonstrate at an intermediate architectural level how call processing is handled. The operational flow of the present invention is not to be viewed as limited to this exemplary illustration.

[0530] FIG. 2B depicts an exemplary call flow 258. FIG. 2B illustrates interaction between a trunking gateway, a soft switch, a configuration server and a route server in order to connect a call through telecommunications network 200.

[0531] FIG. 2B details a call flow from TG 232 of gateway site 108, controlled by soft switch site 104, to TG 234 of gateway site 110, controlled by soft switch site 106. (Soft switch site 106 is illustrated in FIGS. 1 and 3.) Soft switch site 106, including soft switch 304, route server 314, and configuration server 312, is further described below in the Specific Example Embodiments section, with reference to FIG. 3.

[0532] Included in call flow 258 is a description of how soft switch 204 can process a 1+ long distance call that uses project account codes (PACs) with class of service (COS) restrictions. Call flow 258 also assumes that the origination and termination for the call uses SS7 signaling, i.e., that the call comes into network 200 via trunks from carrier facilities 126,130, to trunking gateways 232, 234.

[0533] Exemplary call flow 258 begins with step 259. In step 259, soft switch 204 receives an incoming IAM signaling message from an SS7 GW 208, signaling an incoming call from calling party 102 on carrier facility 126 of a co-carrier.

[0534] In step 260, soft switch 204 sends IPDC commands to trunking gateway 232 to set up a connection (e.g. a DS0 or DS1 circuit) between carrier facility 126 and TG 232 described in the received IAM signaling message. In step 262, trunking gateway 232 sends an acknowledgement message to soft switch 204.

[0535] Based upon the information in the LAM message, soft switch 204 performs initial digit analysis on the dialed number, i.e., the number of called party 120, and determines that the incoming call is a 1+ call.

[0536] In step 263, application program logic within soft switch 204 determines that, with this type of call, i.e., a 1+ call, soft switch 204 should query a customer profile database within configuration server 206, to retrieve the originating customer trigger plan 290 for calling party 102.

[0537] The customer profile lookup is performed in configuration server 206 using the originating automatic number identification (ANI) of calling party 102 as the lookup key.

[0538] In step 264 the customer profile lookup returns to soft switch 204 an indication that the calling party 102 has subscribed to project account codes (PAC). Examples of PACs include billing codes. They provide a mechanism for a network customer, such as a law firm, to keep an accounting of which of their clients to bill. Example call flow 258 will also perform a class of service (COS) restriction, but this will not be known by soft switch 204 until account code verification identifies an associated account code requiring the COS restriction. Alternatively, the customer profile information can reside in route server 212, enabling route server 212 to perform the functions of configuration server 206, in addition to its own functions.

[0539] In step 267, using the information in the customer profile (i.e., customer trigger plans 290) of configuration server 206, soft switch 204 uses the IPDC protocol to instruct trunking gateway 232 to collect the specified number of digits, representing the project account code, from calling party 102.

[0540] In step 268, the digits are sent from trunking gateway 232 to soft switch 204. Assuming that trunking gateway 232 collected the correct number of digits, soft switch 204 uses the customer profile of configuration server 206 to determine how to process the received digits. For project account codes (PACs), the customer profile in configuration server 206 specifies whether the project account code needs to be validated.

[0541] If the project account code settings in the customer profile of configuration server 206 specify that the project account code is “verified and forced,” then soft switch 204, in step 265, can query SCP 214 with the collected digits to verify that they are valid. Table 129 below provides alternative PAC settings.

[0542] In step 266, SCP 214 returns an indication that the project account code is valid, and it requires that an intrastate class of service (COS) restriction should be enforced. The class of service (COS) restriction logic can be performed within soft switch 204, using pre-loaded LATA and state tables from configuration server 206.

[0543] If a PAC is not used, the COS restriction can be applied based on ANI or ingress trunk group.

[0544] If the LATA and state tables from configuration server 206 show that the originating LATA (i.e., the LATA of calling party 102) and the terminating LATA (i.e., the LATA of called party 120) are in the same state, then the call is allowed to proceed.

[0545] At this point, soft switch 204 has finished executing all customer service logic and has a 10-digit DDD number (i.e., the phone number of called party 120), that must be terminated.

[0546] In step 269, soft switch 204 queries route server 212 to receive a call route and to allocate circuits to connect the call. Route server 212 is responsible for using the DDD number to select a least cost route through data network 112, and allocating a terminating circuit for this call.

[0547] Additional information on how soft switch 204 interacts with route server 212 and terminating soft switch 304 is described in the Specific Implementation Example Embodiments Section below, in the section entitled Route Server.

[0548] In step 270, route server 212 returns a route that indicates the connections that soft switch 204 must make to connect the call.

[0549] In step 274, soft switch 204 communicates with soft switch 304 to allocate ports in trunking gateway 234 of gateway site 110, for termination of the call. Soft switch 304 is located in a central soft switch site 106. In step 276, soft switch 304 queries port status 298 of route server 314 to identify available ports in trunking gateway 234. In step 278, route server 314 returns an available port to soft switch 304. In steps 280 and 282, soft switch 304 communicates with trunking gateway 234 to allocate a port for termination of the call to called party 120.

[0550] In step 284, soft switch 304 communicates with soft switch 204 to indicate terminating ports have been allocated.

[0551] In steps 286 and 288, soft switch 204 communicates with trunking gateway 232 in order to notify trunking gateway 232 to set up an RTP session (i.e. an RTP over UDP over IP session) with trunking gateway 234 and to permit call traffic to be passed over data network 112.

[0552] The Specific Implementation Example Embodiments Section, in the next section, describes additional information about, for example, how soft switch 204 performs initial digit analysis to identify the type of call, and how to process the call. The next section also describes how soft switch 204 interacts with other components of the voice network architecture 200 in transmitting the call.

[0553] Various embodiments related to structures, and operations between these structures described above are presented in this section (and its subsections). These embodiments are described herein for purposes of illustration, and not limitation. The invention is not limited to these embodiments. Alternate embodiments (including equivalents, extensions, variations, deviations, etc., of the embodiments described herein) will be apparent to persons skilled in the relevant arts based on the teachings contained herein. The invention is intended and adapted to include such alternate embodiments.

[0554] Specifically, this section provides a detailed description of the VOIP network architecture according to the present invention. A structural implementation of the (VOIP) network architecture is described at a low-level. Also, a functional implementation for this structure is described at a low-level.

[0555] A. Structural Description

[0556] A more detailed structural description of telecommunications network 200 will now be described.

[0557] FIG. 3 is a block diagram illustrating a more detailed implementation of telecommunications network 200. Specifically, FIG. 3 illustrates telecommunications network 300 containing three geographically diverse soft switch sites. These soft switch sites include western soft switch site 104, central soft switch 106, and eastern soft switch 302.

[0558] Telecommunications network 300 also includes a plurality of gateway sites that may be collocated or geographically diverse. These gateway sites include gateway sites 108a, 108b, 110a and 110b.

[0559] Data network 112 can route both signaling and transport traffic between the regional soft switch sites and regional gateway sites. For example, data network 112 can be used to route traffic between western soft switch site 104 and gateway site 110a. Signaling and transport traffic can also be segregated and sent over separate data networks. As those skilled in the art will recognize, data network 112 can be used to establish a data or voice connection among any of the aforementioned gateway sites 108a, 108b, 110a and 110b under the control of any of the aforementioned soft switch sites 104, 106 and 302.

[0560] Western soft switch site 104 includes soft switch 204a, soft switch 204b, and soft switch 204c. Soft switches 204a, 204b, 204c can be collocated or geographically diverse. Soft switches 204a, 204b, 204c provide the features of redundancy and high availability.

[0561] Failover mechanisms are enabled via this architecture, since the soft switches can act as one big switch. Soft switches 204a, 204b, 204c can intercommunicate via the inter soft switch communication protocol, permitting access servers to reconnect from one soft switch to another.

[0562] Western soft switch site 104 includes SS7 gateway (GW) 208, configuration server/configuration database (CS/CDB) 206a and route server (RS) 212a. To provide high availability and redundancy, western soft switch site 104 includes a redundant SS7 GW, a redundant CS/CDB and a redundant RS. Specifically, western soft switch site 104 includes SS7 GW 210, CS/CDB 206b and RS 212b.

[0563] Soft switches 204a, 204b and 204c are connected to SS7 GWs 208, 210, CS/CDBs 206a, 206b and RSs 212a, 212b via redundant ethernet switches (ESs) 332, 334 having multiple redundant paths. This architecture enables centralization of SS7 interconnection to gain economies of scale from use of a lesser number (than conventionally required) of links to signaling network 114, to be shared by many access servers in gateway sites. ESs 332, 334 also provide connectivity to routers (Rs) 320, 322. Routers 320, 322 respectively provide redundant connectivity between redundant ESs 332, 334 and data network 112. As noted, included in telecommunications network 300 are central soft switch site 106 and eastern soft switch site 302. Central soft switch site 106 and eastern soft switch site 302 respectively include identical configurations to the configuration of western soft switch site 104. Central soft switch site 106 includes SS7 GWs 308, CS/CDBs 312, RSs 314, soft switches 304a, 304b, 304c, ESs 336, 338, and Rs 324, 326. Similarly, eastern soft switch site 302 includes SS7 GWs 310, CS/CDBs 316, RSs 318, soft switches 306a, 306b, 306c, ESs 340, 342, and Rs 328 and 330.

[0564] Gateway site 108a includes TG 232a, NAS 228a, AG 238a and DACS 242a. Gateway sites 108b, 110a and 110b have similar configurations to gateway site 108a. Gateway site 108b includes TG 232b, NAS 228b, AG 238b and DACS 242b. Gateway site 110a includes TG 234a, NAS 230a, AG 240a and DACS 244a. Finally, gateway site 110b includes TG 234b, NAS 230b, AG 240b, and DACS 244b. The details of gateway site 108a, 108b, 110a and 110b will be further described below with reference to FIG. 10A.

[0565] Referring back to FIG. 2A, soft switch 204 provides the call processing function for telecommunications network 200. Call processing refers to the handling of voice and data calls. There are a number of important call processing functions handled by soft switch 204. Soft switch 204 processes signaling messages used for call setup and call tear down. These signaling messages can be processed by in-band or out-of-band signaling. For an example of out-of-band signaling, SS7 signaling messages can be transmitted between signaling network 114 and soft switch 204. (Soft switch 204 refers to soft switches 204a, 204b and 204c.)

[0566] Another call processing function performed by soft switch 204 is preliminary digit analysis. Preliminary digit analysis is performed to determine the type of call arriving at soft switch 204. Examples of calls include toll free calls, 1+ calls, 0+ calls, 011+ calls, and other calls recognized by those skilled in the art.

[0567] One important feature of soft switch 204 is communicating with CS/CDB 206 to retrieve important customer information. Specifically, soft switch 204 queries CS/CDB 206 to retrieve a customer trigger plan. The customer trigger plan effectively identifies the service logic to be executed for a given customer.

[0568] This trigger plan is similar to a decision tree pertaining to how a call is to be implemented. Subsequently, soft switch 204 executes the customer trigger plan. This includes the processing of special service calls requiring external call processing, i.e., call processing that is external to the functions of telecommunications network 200.

[0569] Another important function soft switch 204 is communicating with RS 212 to provide network routing information for a customer call. For example, soft switch 204 can query RS 212 to retrieve the route having the least cost from an off-network calling party 102 (homed to gateway site 108) to an off-network called party 120 (homed to gateway site 110) over data network 112. Upon finding the least cost route, soft switch 204 allocates ports on TGs 232, 234. As described in detail below, soft switch 204 can also be used to identify the least cost route termination and allocate gateway ports over AGs 238, 240 between an on-network calling party 122 (homed to gateway site 108) and an on-network called party 124 (homed to gateway site 110).

[0570] Soft switch 204 also communicates with AGs 238, 240, TGs 232, 234, and NASs 228, 230 over data network 112. Although AGs 238, 240, TGs 232, 234 and NASs 228, 230 can communicate with a plurality of soft switches, as illustrated in FIG. 3, these network nodes (referred to collectively as access servers 254a, 254b, 256a, and 256b) are respectively assigned to a primary soft switch. This primary soft switch, e.g., soft switch 204, assumes a primary responsibility or control of the access servers. In addition, the access servers can be as respectively assigned to secondary switches, which control the access servers in the event that the primary soft switch is unavailable.

[0571] Referring back to FIG. 3, western soft switch site 104, central soft switch site 106 and eastern soft switch site 302 are geographically diverse. For example, western soft switch site 104 can be a soft switch site located in San Diego, Calif. Central soft switch site 106 can be a soft switch site located in Denver, Colo. Eastern soft switch site 302 can be a soft switch site located in Boston, Mass.

[0572] It is permissible that additional network nodes are provided at any of soft switch sites 104, 106 and 302. For example, additional elements, including, e.g., SS7 GW 208, CDB 206a, and RS 212a can be collocated at western soft switch site 104. Examples of other supporting elements of western soft switch site 104 are an announcement server (ANS), a network event collection point (NECP), an SCP, and on-network STPs. Referring to the more detailed implementation of FIG. 2A, telecommunications network 200 includes ANSs 246, 248, NECP 224, SCP 214, and STPs 250, 252.

[0573] FIG. 4A is a block diagram illustrating the interfaces between soft switch 204 and the remaining components of telecommunications network 200. The soft switch interfaces of FIG. 4A are provided for exemplary purposes only, and are not to be considered limiting. Soft switch 204 interfaces with SS7 GWs 208, 210 via soft switch-to-SS7 GW interface 402. One example of interface 402 is an SS7 integrated services digital network (ISDN) user part (ISUP) over a transmission control protocol/internet protocol (TCP/IP). Soft switch 204 interfaces with configuration server 206 over interface 406. In an example embodiment, interface 406 is a TCP/IP connection.

[0574] Soft switch 204 interfaces with RNECP 224 over interface 410. In an example embodiment, interface 410 is a TCP/IP connection.

[0575] Soft switch 204 interfaces with route server 212 over interface 408. In an example embodiment, interface 408 is a TCP/IP connection.

[0576] Soft switch 204 interfaces with SCP 214 over interface 404. In an example embodiment, interface 404 is a TCP/IP connection.

[0577] Soft switch 204 interfaces with announcement servers 246, 248 over interface 416. In an example embodiment, interface 416 can include the IPDC protocol used over a TCP/IP connection.

[0578] Soft switch 204 interfaces with TGs 232, 234 over interface 412. In an example embodiment, interface 412 can include the IPDC protocol used over a TCP/IP connection.

[0579] Soft switch 204 interfaces with AGs 238, 240 over interface 414. In an example embodiment, interface 414 can include the IPDC protocol used over a TCP/IP connection.

[0580] In one embodiment, soft switch 204 is an application software program running on a computer. The structure of this exemplary soft switch is an object oriented programming model discussed below with reference to FIGS. 4B-4E.

[0581] Another interface to soft switch 204 (not shown) is a man-machine interface or maintenance and monitoring interface (MMI). MMI can be used as a direct controller for management and machine actions. It should be noted that this is not intended to be the main control interface, but is rather available to accommodate the need for on-site emergency maintenance activities.

[0582] Yet another interface permits communication between soft switches 204, 304. A soft switch-to-soft switch interface will be described further with reference to FIG. 2B. A soft switch 204-to-soft switch 304 interface permits communication between the soft switches 204, 304 that control the originating call-half and terminating call-half of call flow 258. The soft switch 204-to-soft switch 304 interface allows soft switches 204, 304 to set up, tear down and manage voice and data calls. Soft switch 204 to soft switch 304 interface can allow for a plurality of inbound and outbound signaling types including, for example, SS7, ISDN, and in-band E&M signaling.

[0583] In telephony, E&M is a trunking arrangement generally used for two-way (i.e., either side may initiate actions) switch-to-switch or switch-to-network connections. E&M signaling refers to an arrangement that uses separate leads, called respectively the “E” lead and the “M” lead, for signaling and supervisory purposes. The near-end signals the far-end by applying −48 volts DC (“VDC”) to the “M” lead, which results in a ground being applied to the far end's “E” lead. When −48 VDC is applied to the far-end “M” lead, the near-end “E” lead is grounded. “E” lead originally stood for “ear,” i.e., when the near-end “E” lead was grounded, the far end was calling and “wanted your ear.” “M” originally stood for “mouth,” because when the near-end wanted to call (i.e., to speak to) the far end, −48 VDC was applied to that lead.

[0584] When a PBX wishes to connect to another PBX directly, or to a remote PBX or to an extension telephone over a leased voice-grade line (e.g., a channel on a T-1), the PBX can use a special line interface. This special line interface is quite different from that which the PBX uses to interface to directly-attached phones. The basic reason for the difference between a normal extension interface and a long distance interface is that the respective signaling requirements differ. This is true even if the voice signal parameter, such as level and two-wire, four-wire remain the same. When dealing with tie lines or trunks, it is costly, inefficient, and too slow for a PBX to do what an extension telephone would do, i.e., to go off hook, wait for a dial tone, dial, wait for ringing to stop, etc. The E&M tie trunk interface device is a form of standard that exists in the PBX, T-1 multiplexer, voice-digitizer, telephone company world. E&M signaling can take on a plurality of forms. At least five different versions exist. E&M signaling is the most common interface signaling method used to interconnect switching signaling systems with transmission signaling systems.

[0585] The sample configuration depicted in FIG. 2B, can use a soft switch 204-to-soft switch 304 protocol. In FIG. 2B, the access servers depicted are trunking gateways 232, 234. TGs 232, 234 are connected to the switch circuit network (SCN), i.e., signaling network 114, via SS7 trunks, ISDN trunks, and in-band trunks. The originating soft switch 204 can receive a call over any of these trunks. The signaling information from these SS7, ISDN, and in-band trunks is processed by soft switch 204 to establish the originating call-half. The signaling information processed by soft switch 204, can be used to determine the identity of terminating soft switch 304. The identity of terminating soft switch 304 is required to complete the call.

[0586] Originating soft switch 204 can then communicate the necessary information to complete the call, via an inter-soft switch communication (ISSC) protocol. Terminating soft switch 304 can be required to be able to establish the terminating call-half on any of the supported trunk types. The ISSC protocol can use a message set that is structured similarly to the IPDC protocol message set. The messages can contain a header followed by a number of tag-length-value attributes. The incoming signaling message for the call being placed, can be carried in a general data block of one of the attribute value pairs (AVPs). The other AVPs, can contain additional information necessary to establish a voice-over-IP connection between the originating and terminating ends of the call.

[0587] SS7 gateways (GWs) 208, 210 will now be described further with reference to FIG. 2A and FIG. 5A. In FIG. 2A, SS7 GWs 208, 210 receive signaling messages from signaling network 114 and communicate these messages to soft switch 204. Specifically, for SS7 signaled trunks, SS7 GWs 208, 210 can receive SS7 ISUP messages and transfer them to soft switch 204. SS7 GWs 208, 210 can also receive signaling messages from soft switch 204 and send SS7 ISUP messages out to signaling network 114.

[0588] In an example embodiment, SS7 GWs 208, 210 can be deployed in a two (2) computing element (CE) cluster 207, depicted in FIG. 5A. SS7 GWs 208, 210, in two-CE-cluster 207 can fully load-share. SS7 GWs 208, 210 can intercommunicate as represented by connection 530 to balance their loads. Load-sharing results in a completely fault resilient hardware and software system with no single point of failure. Each SS7 GW 208, 210 can have, for example, six two-port cards for a total of twelve links to signaling network 114.

[0589] In an example embodiment, SS7 GWs 208, 210 are application programs running on a computer system. An exemplary application program providing SS7 GW 208, 210 functionality is OMNI SIGNALWARE (OMNI), available from DGM&S, of Mount Laurel, N.J. OMNI is a telecommunications middleware product that runs on a UNIX operating system. An exemplary operating system is the SUN UNIX, available from SUN Microsystems, Inc. of Palo Alto, Calif. The core of OMNI resides logically below the service applications, providing a middleware layer upon which telecommunications applications can be efficiently deployed. Since the operating system is not encapsulated, service applications have direct access to the entire operating environment. Because of OMNI's unique SIGNALWARE architecture, OMNI has the ability to simultaneously support variants of SS7 signaling technology (ITU-T, ANSI, China and Japan).

[0590] The SIGNALWARE architecture core is composed of the Message Transfer Part (MTP) Layer 2 and Layer 3, and Service Connection Control Part (SCCP). These core protocols are supplemented with a higher layer of protocols to meet the needs of a target application or service. OMNI supports multiple protocol stacks simultaneously, each potentially with the point code format and protocol support of one of the major SS7 variants.

[0591] OMNI SIGNALWARE Application Programming Interfaces (APIs) are found on the higher layers of the SS7 protocol stack. OMNI APIs include: ISDN User Part (ISUP), Telephony User Part (TUP), Transaction Capabilities Application Part (TCAP), Global System for Mobile Communications Mobile Application Part (GSM MAP), EIA/TIA Interim Standard 41 (IS-41 MAP), Advanced Intelligent Network (AIN), and Intelligent Network Application Part (INAP).

[0592] FIG. 5A depicts SS7 gateway to soft switch distribution 500. Soft switches receive signaling messages from signaling gateways. Specifically, for SS7 signaled trunks, SS7 GWs 208, 210 send and receive signals from signaling network 114. SS7 GWs 208, 210 communicate with soft switches 204a, 204b, 204c, via redundant connections from the soft switches 204a, 204b, 204c to distributions 508, 510, of SS7 GWs 208, 210 respectively. SS7 GWs 208, 210 together comprise a CE cluster 207.

[0593] Based upon an SS7 network design, a pair of SS7 gateways receive all signaling traffic for the trunking gateway (TG) circuits serviced by the soft switches at a single soft switch site. Specifically, a pair of SS7 GWs 208, 210 receive all signaling traffic for circuits serviced by soft switch site 104. Signals serviced by soft switch site 104 enter telecommunications network 200 from gateway sites 108, 502, 110.

[0594] In an example embodiment, 96 circuits are serviced by each gateway site 108, 502, 110. Gateway site 108 includes TGs 232a, 232b. Gateway site 110 includes TGs 234a, 234b. Gateway site 502 includes TGs 504, 506.

[0595] A circuit is identified by a circuit identification code (CIC). TG 232a includes line card access to a plurality of circuits including CICs 1-48 512 of gateway site 108. TG 232b provides line card access to CICs 49-96 514 of gateway site 108. TG 504 provides line card access to CICs 1-48 516. TG 506 provides line card access to CICs 49-96 518 of gateway site 502. TG 234a provides line card access to CICs 1-48 520. TG 234b provides line card access to CICs 49-96 522 of gateway site 110. Thus, CICs 1-48 512, 516, 520, and CICs 49-96 514, 518, 522 are the trunking gateway circuits serviced by soft switch site 104.

[0596] In an example embodiment, soft switches are partitioned such that any single soft switch will only service a subset of circuits serviced at a given soft switch site. For example, soft switch 204a can service CICs 1-48 512, 516, while soft switch 204b services CICs 49-96 514 and CICs 1-48 520, and soft switch 204c services CICs 49-96 518, 522. In order to assure that all signaling messages for a particular call get to the correct one of soft switches 204a, 204b, 204c, it is necessary to partition SS7 signaling across the available soft switches based upon the circuits that each soft switch services.

[0597] It is much more efficient to run SS7 links to soft switches than to each individual access server (compare to the conventional approach requiring an SS7 link to each SSP). Centralization of SS7 signaling traffic interconnection enables benefits from economies of scale, by requiring less SS7 interconnection links.

[0598] An exemplary technique for distributing circuits across soft switches 204a, 204b, 204c is based upon the originating point code (OPC), destination point code (DPC), and CIC. OPC represents the originating point code for a circuit group, i.e., the point code of a local exchange carrier (LEC) switch, or signal point (SP). For example, the LEC providing CICs 1-48 512, and CICs 49-96 514 can have an OPC 524 of value 777. The LEC providing CICs 1-48 516, and CICs 49-96 518 can have an OPC 526 of value 888. The LEC switch providing CICs 1-48 520, and CICs 49-96 522 has an OPC 528 of value 999. Similarly, DPC represents the destination point code for a circuit group, i.e., the point code of soft switch site 104. Soft switch site 104 has a point code 529 of value 111, and an alternate point code 531 of value 444. Soft switch site 104 can act as one big switch using a flat network design of the present invention. This flat network design simplifies routing of calls.

[0599] To support distribution of circuits across soft switches 204a, 204b, 204c, SS7 GWs 208, 210 can include a lookup table that allows each signaling message to be routed to the correct soft switch 204a, 204b, 204c. The lookup table can route signaling messages to the correct soft switch 204a, 204b, 204c based upon the OPC, DPC, and CIC fields. This lookup table is built on SS7 GWs 208, 210 based upon registration messages coming from soft switches 204a, 204b, 204c.

[0600] In an example embodiment, each time a TG boots up, the TG finds a soft switch to service its circuits. For example, when TG 232a is powered up, TG 232a must find a soft switch 204a, 204b, 204c to service its circuits, i.e. CICs 1-48 512. In an exemplary technique, TG 232a sends registration messages to soft switch 204a to register circuits CICs 1-48 512. Upon receipt of these registration messages the soft switch 204a registers these circuits with SS7 GWs 208, 210, at soft switch site 104. The circuit registration messages sent to the SS7 gateways are used to build the type of table shown in Table 6.

[0601]

TABLE 6
OPC, DPC, CIC
registration request	Value
Message Type	SS7 gateway circuit registration
OPC	Originating point code for the circuit group.
	Equals the LEC point code.
Primary DPC	Primary destination point code for the circuit
	group. Equals the Soft Switch site point
	code.
Alias DPC	Alias DPC for the Soft Switch site
Start CIC	Starting Circuit Identification Code for the
	circuit group
End CIC	Ending Circuit Identification Code for the
	circuit group
Servicing Soft Switch ID	Unique Identifier for the Soft Switch that
	will service requests for the OPC, DPC, CIC
	values
Servicing Soft Switch	IP address for the Soft Switch that will
IP address	service requests for the OPC, DPC, CIC
	values
Servicing Soft Switch	Port number that the Soft Switch is listening
IP port	on for incoming signaling messages.
Primary/Secondary/Tertiary	The Soft Switch identifies itself as the
identification	primary, secondary or tertiary contact for
	signaling messages for the specified OPC,
	DPC and CIC.

[0602] The format of a registration message is shown in Table 7. Table 7 includes the mapping of circuits to soft switches.

[0603] The messages used by soft switches 204a, 204b, 204c to register their circuits with SS7 GWs 208, 210 contain information for the OPC, DPC and circuit range, i.e., the CICs that are being registered. Each message also contains information about the soft switch that will be servicing the signaling messages for the circuits being registered.

[0604] The soft switch information includes an indication of whether this soft switch is identified as the primary servicing point for calls to these circuits, the secondary servicing point or the tertiary servicing point. The gateway uses this indicator in failure conditions, when it cannot contact the Soft Switch that is currently servicing a set of circuits.

[0605]

	TABLE 7
			CIC	Soft
	OPC	DPC	range	Switch
	777	111	1-48	204a
	777	111	49–96	204b
	888	111	1-48	204a
	888	111	49–96	204c
	999	111	1-48	204b
	999	111	49–96	204c

[0606] FIG. 5A illustrates, and Table 7 represents in tabular form, the associations between circuit trunk groups of TGs 232a, 232b, 516, 518, 520, 522 and soft switches 204a, 204b, 204c. SS7 GWs 208, 210 distribute incoming SS7 signaling messages to the soft switch 204a, 204b, 204c listed as associated with the particular circuit in the circuit to soft switch mapping lookup table, (i.e., Table 7). For example, when the LEC switch, or signaling point, associated with OPC 524 (having point code 777) sends a call to TG 232b over CIC 55 (of CICs 49-96 514), an IAM message can be created and routed. The IAM includes the following information:

• • [0607] (1) OPC 777 (originating LEC has a point code 777),
  • [0608] (2) DPC 111 (soft switch site 104, the “switch” that the LEC believes it is trunking to, has point code 111), and
  • [0609] (3) CIC 55 (the circuit selected by the LEC has circuit identifier code 55).

[0610] The IAM message can then be routed by signaling network 114 (i.e., the SS7 network) to SS7 GWs 208, 210 at soft switch site 104, having point code 111. SS7 GWs 208, 210 can perform a lookup to Table 7, to identify which of soft switches 204a, 204b, 204c is handling the particular circuit described in the IAM message. In the example above, the IAM message having OPC 524 of value 777, DPC of value 111 and CIC 55 can be routed to soft switch 204b.

[0611] SS7 GWs 208, 210 will now be discussed further with reference to FIG. 17A. FIG. 17A depicts an exemplary signaling network environment 1700. FIG. 17A includes signaling network 114 Specifically, signaling network 114 can be an SS7 national signaling network. FIG. 17A depicts three soft switch sites interfacing via a plurality of STPs to SS7 network 114.

[0612] FIG. 17A includes soft switch sites 104, 106, 302. Western soft switch site 104 includes three soft switches 204a, 204b, 204c redundantly connected to routers 320, 322 and SS7 GWs 208, 210 via ethernet switches 332, 334. SS7 GW 208 and SS7 GW 210 communicate via a TCP/IP connection 1702 and serial link 1704.

[0613] Similarly, central soft switch site 106 includes soft switches 304a, 304b, 304c redundantly connected to routers 324, 326 and SS7 GWs 308a, 308b via ethernet switches 336, 338. SS7 GW 308a and SS7 GW 308b communicate via TCP/IP connection 1706 and serial link 1708.

[0614] Finally, eastern soft switch site 302 includes soft switches 306a, 306b, 306c redundantly connected to routers 328, 330 and SS7 GWs 310a, 310b via ethernet switches 340, 342. SS7 GW 310a and SS7 GW 310b communicate via TCP/IP connection 1710 and serial link 1712.

[0615] FIG. 17A also includes data network 112 connected to soft switch sites 104, 106, 302 via routers 320, 322, routers 324, 326 and routers 328, 330, respectively. Data network 112 can carry data including control message information and call traffic information. Data network 112 can also carry in-band type signaling information and ISDN signaling information, via IPDC messages.

[0616] Out-of-band signaling, such as, e.g., SS7 signaling, information is communicated to (i.e. exchanged with) soft switch sites 104, 106, 302 via SS7 GWs 208, 210, SS7 GWs 308a, 308b, and SS7 GWs 310a, 310b from signaling network 114.

[0617] SS7 signaling messages are transferred through signaling network 114 from STP to STP until arriving at a final destination. Specifically, signaling messages intended for soft switch sites 104, 106, 302, are routed via packet switched SS7 signaling network 114 to STPs 216, 218 which are part of the SS7 national signaling network 114. STP services (i.e., STPs and A-F links) can be provided: by an SS7 signaling services provider, such as, e.g., Transaction Network Services (TNS).

[0618] Table 19 defines SS7 signaling links. Some of the SS7 links used are as follows. STPs 216, 218 are linked together by a C-link. STPs 216, 218 are linked by redundant D-links 1730 to STPs 250a, 252a, 1722, 1724, 250b, 252b. STPs 216, 218 can also be linked by redundant D-links 1730 to STPs 1718, 1720, 1714, 1716, though this is not shown.

[0619] STP pairs 250a, 252a are linked together by one or more C-links 1728. Likewise, STP pairs 1722, 1724, STP pairs 250b, 252b, STP pairs 1718, 1720, and STP pairs 1714, 1716 can be linked together by C-links.

[0620] STPs 1714, 1716, 250a, 252a, 1722, 1724, 250b, 252b, 1718, and 1720 can be linked by one or more A-links 1726 to SS7 GWs 208, 210, 308a, 308b, 310a, and 310b. Thus, signaling messages from anywhere in signaling network 114 may be routed by STPs 216, 218 through STPs 1714, 1716, 250a, 252a, 1722, 1724, 250b, 252b, 1718, 1720, to SS7 GWs 208, 210, 308a, 308b, 310a, and 310b of soft switch sites 104, 106, and 302. SS7 GWs 208, 210, 308a, 308b, 310a, and 310b thus route messages through packet switched STPs to signaling network 114.

[0621] SS7 GWs 208, 210, 308a, 308b, 310a, and 310b use a separate physical interface for all simple network management protocol (SNMP) messages and additional functions that may be defined. Exemplary functions that may be defined include provisioning, updating, and passing special alarms, and performance parameters to the SS7 GW from the network operation center (NOC) of network management component 118.

[0622] Signal transfer points (STPs) 216, 218 are the packet switches of signaling network 114. More specifically, STPs are the packet switches of the SS7 network. STPs 250, 252 are the STPs interfacing with SS7 GCs 208, 210 of soft switch site 104. STPs 216, 218 receive and route incoming signaling messages toward the proper destination.

[0623] STPs 250, 252 also perform specialized routing functions. STPs are customarily deployed in pairs. While elements of a pair are not generally collocated, they work redundantly to perform the same logical function.

[0624] STPs have several interfaces. STP interfaces are now described, with reference to FIGS. 17A and 17B. The interfaces can be described in terms of the links used. Table 19 shows links used in SS7 architectures.

[0625] The first interface comprises one or more D-links 1730 from off-network STPs 250, 252 (as shown in FIG. 2A) to on-network STPs 216, 218. D-links connect mated STPs at different hierarchical levels to one another. On-network STPs 216, 218, as well as STPs 1714, 1716, 1722, 1724, 1718 and 1720 are part of the national SS7 signaling network 114. Additional D-links 1730 can connect STPs 216, 218 to STPs 250a, 252a, STPs 1722, 1724, STPs 250b, 252b, and STPs 1718 and 1720.

[0626] The second interface comprises C-links. C-links connect mated STPs together. An example are C-links 1728 between STP 250a and 252a. C-links 1728 enable STPs 250a, 252a to be linked in such a manner that they need not be co-located. Similarly, STPs 250b, 252b, STPs 1718, 1720, STPs 1722, 1724, STPs 1714, 1716, and STPs 216, 218 can also be respectively linked via C-links.

[0627] The third interfaces to STPs comprise A-links and E-links. A-links connect STPs to SSPs and SCPs. E-links are special links that connect SSPs to remote STPs, and are used in the event that A-links to home STPs are congested. The entire soft switch site is viewed as an SSP to a signaling network. A-links or E-links can be used to connect any of STPs 1714, 1716, 250a, 252a, 1722, 1724, 250b, 252b, 1718 and 1720 respectively to soft switch sites 104, 106, 302 at SS7 GWs 208, 210, 308a, 308b, 310a and 310b. In an example embodiment, each of SS7 GWs 208, 210, 308a, 308b, 310a, 310b can have, for example, twelve (12) A-links 1726 distributed among STPs 250a, 252a, 250b, 252b and STPs 1714, 1716, 1722, 1724, 1718, 1720. By using the plurality of A-links, the soft switch sites 104, 106, 302 have a fully redundant, fully meshed, fault tolerant signaling architecture.

[0628] STPs 250a, 252a, 250b, 252b use a separate physical interface for all SNMP messages and additional functions that can be defined. Additional functions that can be defined include provisioning, updating, and passing special alarms and performance parameters to and from STPs 250a, 252a, 250b, 252b and network operation center (NOC) of network management component 118.

[0629] In another embodiment of the invention, as illustrated in FIG. 17B, soft switch sites 104, 106, 302 have additional soft switches and SS7 GWs. Additional soft switches and SS7 GWs can be used, for example, for handling additional traffic and for testing of alternative vendor soft switches and SS7 GWs.

[0630] FIG. 17B includes SS7 gateway to SS7 signaling network alternative embodiment 1740. FIG. 17B includes signaling network 114 interfacing to western soft switch site 104, central soft switch site 106, and eastern soft switch site 302. Signaling network 114 includes STPs 216, 218 connected via multiple D-Links 1730 to STPs 250a, 252a, 250b, 252b. In an example embodiment STP 250a and STP 252a are connected together by C-Links 1728. In an alternative embodiment, STPs 250a, 252a and STPs 250b, 252b can be linked by quad B-Links. B-links connect mated STP pairs to other mated STP pairs. STPs 250a, 252a, 250b, 252b are connected by multiple redundants A-Links 1726 to SS7 GWs in soft switch sites 104, 106, 302.

[0631] Western soft switch site 104 includes SS7 GWs 208, 210, which can communicate via a TCP/IP connection and a serial link. SS7 GWs 208, 210 are connected to soft switches 204a, 204b, and 204c. In addition, western soft switch site 104 includes soft switch 1742 and SS7 GW 1744 connected to STPs 250a and 252a. Also western soft switch site 104 includes soft switch 1746 and SS7 GW 1748 connected to STPs 250a, 252a.

[0632] Central soft switch site 106 includes SS7 GWs 308a, 308B which can communicate via a TCP/IP connection or a serial link. SS7 GWs 308a, 308b connect soft switches 304a, 304b and 304c to STPs 250a and 252a. Central soft switch site 106 also includes soft switch 1750 and SS7 GWs 1752 connected to STPs 250a, 252a. Central soft switch site 106 also includes soft switch 1754 connected to SS7 GW 1756, which is connected to STPs 250a, 252a.

[0633] Eastern soft switch site 302 includes SS7 GWs 310a, SS7 GW 310b, which can communicate over TCP/IP and over a serial link. SS7 GWs 310a, 310b connect soft switches 306a, 306b and 306c to STPs 250b and 252b. Eastern soft switch site 302 also includes soft switch 1758 connected to SS7 GW 1760, which is connected to STPs 250b, 252b. Eastern soft switch site 302 also includes soft switch 1762, which is connected to SS7 GW 1764 which is in turn connected to STPs 250b, 252b.

[0634] Alternative embodiment 1740, by including additional soft switches and SS7 gateways, permits additional redundancy and enables testing of alternate devices for connection to signaling network 114 via STPs 250a, 252a, 250b, 252b, 216 and 218.

[0635] STPs 250, 252, in an example embodiment, can be a TEKELEC Network Switching Division's EAGLE STP. An EAGLE STP, available from TEKELEC of Calabasas, Calif., is a high speed packet switch designed to support SS7 signaling. STPs 250, 252 can be equipped with a plurality of links. In an example embodiment, STPs 250, 252 can support up to, for example, 84 links. For example, in a preferred embodiment, 14 links can be used initially, and additional links can be added in the future. In a preferred embodiment, several additional features can be added to STPs 250, 252.

[0636] In a preferred embodiment, STPs 250, 252 can have global title translation capability. Global title translation uses global title information. Global title information is information unrelated to signaling network address, which can be used to determine the appropriate destination of a message. Global title translation can support translations from, for example, one to twenty-one digits. For example, translations can be assigned to translation types from 0 to 225. In a preferred embodiment, STPs 250, 252 can support up to, for example, 1,000 global title translation requests per second, per application service module (ASM).

[0637] In a preferred embodiment, STPs 250, 252 include a gateway screening software feature. EAGLE STP can support user definitions of up to 64 screen sets In this embodiment, each screen set can accommodate up to 2,000 condition statements (or rules) with the gateway screening software. Gateway screening can be performed on all in-bound messages from another network. Gateway screening can also be performed on all outgoing network management messages. Since gateway screening can occur on the link interface modules (LIMs) and the application service modules (ASMs), the deployment of the gateway screening feature does not impact link throughput capacity, and can contribute to less than 5 milliseconds increase to cross-STP delays.

[0638] In a preferred embodiment, local number portability (LNP) can be integrated into the EAGLE architecture of STPs 250, 252. An advantage of the integration of LNP functionality is that it eliminates the need for costly external LNP databases, and associated transmission equipment. In one embodiment, LNP portability can support, complete scalabilty in configurations ranging from 500,000 translation entries and up to more than several million translation entries for very large metropolitan serving areas (MSAs).

[0639] In a preferred embodiment, the STP-to-LAN interface of the EAGLE architecture can allow the user to connect external data collection or processing systems directly to STPs 250, 252 via a TCP/IP protocol. In this embodiment, the STP-to-LAN interface could be used to carry SS7 signaling over IP packets.

[0640] In a preferred embodiment, STPs 250, 252 can include a feature referred to as the ANSI-ITU gateway feature. In a preferred embodiment, the ANSI-ITU feature of STPs 250, 252 allows STPs 250, 252 to interconnect three types of signaling networks, i.e., ITU international, ITU national and ANSI, by means of three different message signaling unit (MSU) protocols. In a preferred embodiment of STPs 250, 252, the ANSI-ITU feature can allow a smooth transition from an all-ANSI network to a combined ANSI-ITU network.

[0641] FIG. 6A depicts off-switch called processing abstraction diagram 600 showing communication mechanisms between soft switch and STPs. FIG. 6A includes at the gateway-facing layer, soft switch processing 604 which can use the IPDC protocol 602, or alternatively, the Network Access Server (NAS) Messaging Interface (NMI) protocol to interface with access servers, or the messaging gateway control protocol (MGCP). IPDC protocol 602 provides a protocol for communications between soft switches and respectively TGs, AGs, NASs and ANSs. Soft switch processing 604 uses IPDC for gateway communication and uses off-switch call processing 606 to access SCPs 608, 614, 618, 620.

[0642] SS7 TCAP 608 is connected to SCP 610 an off-network SCP, via STP 250. IP TCAP 614 is connected to SCP 612. SCP 616 is connected to custom IP 618. SCP 214 is an on-network SCP and is connected via INAP/IP 620.

[0643] FIG. 6A represents how some interfaces to soft switch 204 sit on top of a common interface used by soft switch 204 to handle off-switch call processing. SCPs and other devices, such as route servers, can use this common interface. For example, SCP 610 is an off-network or off-switch SCP, meaning that it is not within soft switch site 104.

[0644] Off-switch call processing abstraction layer 606 is intended to be a flexible interface, similar to TCAP in function, that allows interaction between any type of SCP (or other call processing logic) and soft switch 204. The abstraction layer is so designed that interfaces to a set of call processors supporting a specific function (e.g., 800 service), contain the same types of data, and can all map arguments to data elements supported by off-switch call processing abstraction layer 606. The field values for messages supplied by off-switch call processing abstraction layer 606 are identified in this section (i.e., describing SCPs) and also in the section describing route servers below.

[0645] The SCPs can be off-switch call processing servers, which support intelligent services within the telecommunications network SCPs 610, 612, and 616 can support such services as, for example, account code verification and toll free/800 services, local number portability (LNP), carrier ID identification, and card services.

[0646] Other services and capabilities of SCPs 610, 612, and 616 include basic toll-free services, project account code (PAC) services, local number portability (LNP) services, 800 carrier ID services, calling name (CNAM) services, advanced toll-free/network automatic call distribution (ACD) services, customer premise toll-free routing services, one number (or follow-me) services, and SCP gateway for customer premises equipment (CPE) route selection services. These services are recognized by those skilled in the art.

[0647] Additional services and capabilities can include intelligent peripherals. Intelligent peripherals can include calling card, debit card, voicemail, unified messaging, conference calling, and operator services. These peripherals are recognized by those skilled in the art.

[0648] FIG. 6B illustrates intelligent network architecture 622. FIG. 6B includes gateway site 110, communicating via data network 112, to soft switch 204. The communication can be performed by the H.323 protocol or the IPDC protocol. Soft switch 204 gains signaling information from signaling network 114 via STP 250, through SS7 gateway 208.

[0649] Gateway site 110, in intelligent network architecture 622, is connected to multiple off-network service providers. Off network service providers include local exchange carrier (LEC) 624, inter-exchange (IXC) carrier 626 and operator services service bureau 628. Thus calls coming in from LEC 624 or from IXC 626 into gateway site 110, if identified as an operator call, may be routed to off-network operator services 628.

[0650] Soft switch 204 does not dictate any particular SCP interface, but it is assumed that this interface will support the following types of interactions: (1) route request; (2) route response; (3) call gapping; and (4) connect to resource.

[0651] A route request is a message sent from soft switch 204 to an external SCP 610. The route request is sent to request a translation service from SCP 610, for example, to translate disclosed digits to a destination number.

[0652] A route response is a message sent from SCP 610 to soft switch 204 in response to a route request. The route response includes a sequence of prioritized destinations for the call. SCPs that perform routing can return a list of prioritized destinations. These destinations can be, for example, any combination of destination numbers or circuit groups. If SCP 610 returns a destinations number, soft switch 204 can attempt to route to that destination number using the least cost routing logic included in route server 212. If SCP 610 returns a circuit group, the soft switch 204 can use route server 212 to select an available circuit in that group. Soft switch 204 can try to terminate to the specified destinations in the prioritized order that the destinations are returned from SCP 610.

[0653] The interface that can be used by soft switch 204, in order to interact with SCPs 214, 610, 612, and 616, is called the off-switch call processing (OSCP) interface. This interface is also used for route server 212 and any other call processing engines. OSCP is represented in FIG. 6A as off-switch call processing abstraction layer 606. Tables 8, 9, 10, and 11 identify the fields in the OSCP route request and route response messages, which are necessary for 800 and account code processing service calls.

[0654]

TABLE 8
800 Route Request
SCP Route
Request Parameter	800 SCP - Route Request Value
Message Type	800 Route Request
Call Reference	Unique call identifier
Requesting Soft-Switch	Soft Switch ID
Bearer Capability	Voice, Data or Fax
Destination type	DDD (an 8XX number was dialed)
Destination	Dialed 8XX number
Originating LATA	LATA from IAM or from DAL profile
Calling Number	ANI
Originating station type	II-digits from IAM or DAL profile
Collected Digits	Not Used for 800 processing

[0655]

TABLE 9
Account Code Route Request
OSCP Route
Request Parameter	Account Code SCP - Route Request Value
Message Type	Account Code Route Request
Call Reference	Unique call identifier
Requesting Soft-Switch	Soft Switch ID
Bearer Capability	Not used for Account Code processing
Destination type	Not used for Account Code processing
Destination	Not used for Account Code processing
Originating LATA	LATA from IAM or from DAL profile
Calling Number	ANI
Originating station type	II-digits from IAM or DAL profile
Collected Digits	Not Used for Account Code processing

[0656]

TABLE 10
800 Route Response
OSCP Route Request Parameter	800 SCP-Route Response Value
Message Type	800 Route Response
Call Reference	Unique call identifier
Result Code	Success/fail
Number of responses	Number of responses sent from the SCP
Destination circuit group - 1	Terminating circuit group for the
	first route if the SCP identifies
	circuit groups
Destination circuit - 1	Not used for 800 processing
Outpulse digits - 1	Outpulse digits for selected
	termination
Destination number - 1	Destination number for the first route
Destination Soft Switch - 1	Not used for 800 processing
Destination circuit group - N	Terminating circuit group for the Nth
	route, if the SCP identifies circuit
	groups
Destination circuit - N	Not used for 800 processing
Outpulse digits - N	Outpulse digit format for selected
	circuit on the Nth route
Destination number - N	Destination number for the Nth route
Destination Soft Switch - N	Not used for 800 processing

[0657]

TABLE 11
Account Code Route Response
	Account Code SCP-Route
OSCP Route Request Parameter	Response Value
Call Reference	Unique call identifier
Result Code	Success/fail
Number of responses	0 - this is a success/fail response
Destination circuit group - 1	Not used for account code processing
Destination circuit - 1	Not used for account code processing
Outpulse digits - 1	Not used for account code processing
Destination number - 1	Not used for account code processing
Destination Soft Switch - 1	Not used for account code processing
Destination circuit group - N	Not used for account code processing
Destination circuit - N	Not used for account code processing
Outpulse digits - N	Not used for account code processing
Destination number - N	Not used for account code processing
Destination Soft Switch - N	Not used for account code processing

[0658] A route response can also include an indication to initiate a call gapping for a congested call. Call gapping refers to a message sent from an SCP to a soft switch to control the number and frequency of requests sent to that SCP. The call gapping response can indicate a length of time for which gapping should be active, as well as a gap interval, at which the soft switch should space requests going to the SCP. Call gapping can be activated on the SCP for each individual service supported on the SCP. For example, if SCP 214 supports 800 and project account code queries, it may gap on 800, but not or project account codes. Alternatively, SCP 214 can gap on project codes but not on 800, or can gap on both or neither.

[0659] A connect-to resource is a response that is sent from the SCP to the soft switch in response to a route request for requests that require a call termination announcement to be played.

[0660] FIG. 6C illustrates additional off-switch services 630. For example, calling card interactive voice response (IVR) 632 services can be provided off-switch, similarly to operator services 628. FIG. 6C also depicts on-switch SCP services. Specifically, project account codes (PAC) SCP 214a and basic toll-free SCP 214b communicate with soft switch 204 via an INAP/IP protocol 620. Project account codes are discussed further below. Basic toll-free services are also discussed further below.

[0661] FIG. 6D depicts additional services 634. For example, FIG. 6D depicts service node/IP 656, which can be a voice services platform with a voice over IP (VOIP) interface on data network 112. In addition, network IVR 654 is depicted. Network IVR 654 is an IVR that connects to data network 112. Network IVR 654 can communicate with soft switch 204 via the IPDC protocol. Network IVR 654 is also in communication with an advanced toll-free SCP 648, via the SR-3511 protocol.

[0662] Advanced toll-free SCP 648 is in communication with soft switch 204 via INAP/IP protocol 620. Advanced toll-free SCP 648 is also in communication with computer telephony integration (CTI) server 650. CTI server 650 can communicate with an automatic call distributor (ACD) 652.

[0663] FIG. 6D also depicts an IP client connected via a customer network into data network 112. Specifically, IP-Client 660 is connected to data network 112 via customer network 658. Customer network 658 is connected to data network 112 and communicates via an H.323 protocol or via IPDC protocol 602 through data network 112 to soft switch 204. Soft switch 204 is in communication with SS7 gateway 208 via a TCAP/SS7 608 protocol. SS7 gateway 208 is in turn in communication with STP 208 via a TCAP/SS7 608 protocol. STP 208 in turn can communicate with SCPs in the SS7 network via the TCAP/SS7 608 protocol. Specifically, STP 208 can communicate with local number portability (LNP) SCP 636 and also 800 carrier SCP 610. Soft switch 204 can still communicate with PAC SCP 214A and basic toll-free SCP 214B via an INAP/IP 620 protocol. Soft switch 204 can also communicate with an SCP gateway 638 via an INAP/IP 620 protocol. SCP gateway 638 can be used to communicate with customer premises toll-free 640 facilities. Customer premises toll-free 640 facilities can communicate with computer telephony integration (CTI) server 642. CTI server 642 can be in communication with an automatic call distributer (ACD) 644.

[0664] The H.323 Recommendation will now be briefly overviewed The H.323 standard provides a foundation for, for example, audio, video, and data communications across IP-based networks, including the Internet. By complying with the H.323 Recommendation, multimedia products and applications from multiple vendors can interoperate, allowing users to communicate without concern for compatibility. H.323 will be the foundation of future LAN-based products for consumer, business, entertainment, and professional applications.

[0665] H.323 is an umbrella recommendation from the International Telecommunications Union (ITU) that sets standards for multimedia communications over Local Area Networks (LANs) that do not provide a guaranteed Quality of Service (QoS). These networks dominate today's corporate desktops and include packet-switched TCP/IP and IPX over Ethernet, Fast Ethernet and Token Ring network technologies. Therefore, the H.323 standards are important building blocks for a broad new range of collaborative, LAN-based applications for multimedia communications.

[0666] The H.323 specification was approved in 1996 by the ITU's Study Group 16. Version 2 was approved in January 1998. The standard is broad in scope and includes both stand-alone devices and embedded personal computer technology as well as point-to-point and multipoint conferences. H.323 also addresses call control, multimedia management, and bandwidth management as well as interfaces between LANs and other networks.

[0667] H.323 is part of a larger series of communications standards that enable videoconferencing across a range of networks. Known as H.32X this series includes H.320 and H.324, which address ISDN and PSTN communications, respectively.

[0668] FIG. 58A depicts a block diagram of the H.323 architecture for a network-based communications system 5800. H.323 defines four major components for network-based communications system 5800, including: terminals 5802, 5804 and 5810, gateways 5806, gatekeepers 5808, and multipoint control units 5812.

[0669] Terminals 5802, 5804, 5810 are the client endpoints on the LAN that provide real-time, two-way communications. All terminals must support voice communications; video and data are optional. H.323 specifies the modes of operation required for different audio, video, and/or data terminals to work together. It is the dominant standard of the next generation of Internet phones, audio conferencing terminals, and video conferencing technologies.

[0670] All H.323 terminals must also support H.245, which is used to negotiate channel usage and capabilities. FIG. 58B depicts an exemplary H.323 terminal 5802. Three other components are required: Q.931 for call signaling and call setup, a component called Registration/Admission/Status (RAS), which is a protocol used to communicate with a gatekeeper 5808; and support for RTP/RTCP for sequencing audio and video packets.

[0671] Optional components in an H.323 terminal are video codecs, T.120 data conferencing protocols, and MCU capabilities (described further below).

[0672] Gateway 5806 is an optional element in an H.323 conference. FIG. 59 depicts an example H.323 gateway. Gateways 5806 provide many services, the most common being a translation function between H.323 conferencing endpoints and other terminal types. This function includes translation between transmission formats (i.e. H.225.0 to H.221) and between communications procedures (i.e. H.245 to H.242). In addition, gateway 5806 also translates between audio and video codecs and performs call setup and clearing on both the LAN side and the switched-circuit network side. FIG. 59 shows an H.323/PSTN Gateway 5806.

[0673] In general, the purpose of gateway 5806 is to reflect the characteristics of a LAN endpoint to an SCN endpoint and vice versa. The primary applications of gateways 5806 are likely to be:

• • [0674] Establishing links with analog PSTN terminals.
  • [0675] Establishing links with remote H.320-compliant terminals over ISDN-based switched-circuit networks.
  • [0676] Establishing links with remote H.324-compliant terminals over PSTN networks

[0677] Gateways 5806 are not required if connections to other networks are not needed, since endpoints may directly communicate with other endpoints on the same LAN. Terminals communicate with gateways 5806 using the H.245 and Q.931 protocols.

[0678] With the appropriate transcoders, H.323 gateways 5806 can support terminals that comply with H.310, H.321, H.322, and V.70.

[0679] Many gateway 5806 functions are left to the designer. For example, the actual number of H.323 terminals that can communicate through the gateway is not subject to standardization. Similarly, the number of SCN connections, the number of simultaneous independent conferences supported, the audio/video/data conversion functions, and inclusion of multipoint functions are left to the manufacturer. By incorporating gateway 5806 technology into the H.323 specification, the ITU has positioned H.323 as the glue that holds the world of standards-based conferencing endpoints together.

[0680] Gatekeeper 5808 is the most important component of an H.323 enabled network. It acts as the central point for all calls within its zone and provides call control services to registered endpoints. In many ways, an H.323 gatekeeper 5808 acts as a virtual switch.

[0681] Gatekeepers 5808 perform two important call control functions. The first is address translation from LAN aliases for terminals and gateways to IP or IPX addresses, as defined in the RAS specification. The second function is bandwidth management, which is also designated within RAS. For instance, if a network manager has specified a threshold for the number of simultaneous conferences on the LAN, the Gatekeeper 5808 can refuse to make any more connections once the threshold is reached. The effect is to limit the total conferencing bandwidth to some fraction of the total available; the remaining capacity is left for e-mail, file transfers, and other LAN protocols. FIG. 60 depicts a collection of all terminals, gateways 5806, and multipoint control units 5812 which can be managed by a single gatekeeper 5808. This collection of elements is known as an H.323 Zone.

[0682] An optional, but valuable feature of a gatekeeper 5808 is its ability to route H.323 calls. By routing a call through a gatekeeper, it can be controlled more effectively. Service providers need this ability in order to bill for calls placed through their network. This service can also be used to re-route a call to another endpoint if a called endpoint is unavailable. In addition, a gatekeeper 5808 capable of routing H.323 calls can help make decisions involving balancing among multiple gateways. For instance, if a call is routed through a gatekeeper 5808, that gatekeeper 5808 can the re-route the call to one of many gateways based on some proprietary routing logic.

[0683] While a gatekeeper 5808 is logically separate from H.323 endpoints, vendors can incorporate gatekeeper 5808 functionality into the physical implementation of gateways 5806 and MCUs 5812.

[0684] Gatekeeper 5808 is not required in an H.323 system. However, if a gatekeeper 5808 is present, terminals must make use of the services offered by gatekeepers 5808. RAS defines these as address translation, admissions control, bandwidth control, and zone management.

[0685] Gatekeepers 5808 can also play a role in multipoint connections. To support multipoint conferences, users would employ a Gatekeeper 5808 to receive H.245 Control Channels from two terminals in a point-to-point conference. When the conference switches to multipoint, the gatekeeper can redirect the H.245 Control Channel to a multipoint controller, the MC. Gatekeeper 5808 need not process the H.245 signaling; it only needs to pass it between the terminals 5802, 5804, 5808 or the terminals and the MC.

[0686] LANs which contain Gateways 5806 could also contain a gatekeeper 5808 to translate incoming E.164 addresses into Transport Addresses. Because a Zone is defined by its gatekeeper 5808, H.323 entities that contain an internal gatekeeper 5808 require a mechanism to disable the internal function so that when there are multiple H.323 entities that contain a gatekeeper 5808 on a LAN, the entities can be configured into the same Zone.

[0687] The Multipoint Control Unit (MCU) 5812 supports conferences between three or more endpoints. Under H.323, an MCU 5812 consists of a Multipoint Controller (MC), which is required, and zero or more Multipoint Processors (MP). The MC handles H.245 negotiations between all terminals to determine common capabilities for audio and video processing. The MC also controls conference resources by determining which, if any, of the audio and video streams will be muiticast. MCU 2112 is depicted in FIG. 61.

[0688] The MC does not deal directly with any of the media streams. This is left to the MP, which mixes, switches, and processes audio, video, and/or data bits. MC and MP capabilities can exist in a dedicated component or be part of other H.323 components. A soft switch includes some functions of an MP. An access server, also sometimes referred to as a media gateway controller, includes some of the functions of the MC. MCs and MPs are discussed further below with respect to the IPDC protocol.

[0689] Approved in January of 1998, version 2 of the H.323 standard addresses deficiencies in version 1 and introduces new functionality within existing protocols, such as Q.931, H.245 and H.225, as well as entirely new protocols. The most significant advances were in security, fast call setup, supplementary services and T.120/H.323 integration.

[0690] Project Account Codes can be used for tracking calls for billing, invoicing, and Class of Service (COS) restrictions. Project account code (PAC) verifications can include, for example, types Unverified Unforced, Unverified Forced, Verified Forced, and Partially Verified Forced. A web interface can be provided for a business customer to manage its accounts. The business customer can use the web interface to make additions, deletions, changes, and modifications to PAC translations without involvement of a carrier's customer service department.

[0691] An example of call processing using PACs follows. PAC SCP 214a of FIG. 6C can receive validation requests from Soft-Switch 204 after Soft-Switch 204 has requested and received PAC digits. The PAC digits can be forwarded to SCP 214a for verification. When SCP 214a receives this request, SCP 214a can compare the entire PAC, if the PAC type is Verified Forced, against a customer PAC table. SCP 214a can compare only the verified portion of the PAC, if the PAC type is Partially Verified Forced, against the customer PAC table.

[0692] The PAC digits can be sent from Soft-Switch 204 to SCP 214a in the ‘Caller Entered Digits’ field. The indicated customer can be sent from Soft-Switch 204 to SCP 214a in the ‘Customer’ field.

[0693] Basic Toll-Free Service SCP 214b can translate a toll free (e.g., 800 and 888) number to a final routing destination based on a flexible set of options selected by a subscriber. Basic toll-free service supports e.g., 800 and 8XX Service Access Codes. Subscriber options can include, for example: 1) routing based on NPA or NPA-NXX of calling party; 2) routing based on time of day and day of week; 3) routing based on percent distribution; 4) emergency override routing; and 5) blocking based on calling party's NPA or NPA-NXX or ii-digits.

[0694] An exemplary embodiment of basic toll-free SCP 214b is a GENESYS Network Interaction Router available from GENESYS of San Francisco, Calif. The GENESYS Network Interaction Router product suite provides Basic Toll-Free service. Soft-Switch 204 can send route requests to SCP 214b for any Toll Free numbers that Soft-Switch 204 receives. SCP 214b can then attempt to route the call using a route plan or trigger plan that has been defined for that Toll Free (dialed) number. SCP 214b can have several possible responses to a soft switch routing request, see Table 10 above. Using the subscriber routing option (described in the previous paragraph) SCP 214b can return a number translation for the Toll Free number. For example, SCP 214b can receive a dialed number of 800-202-2020 and return a DDD such as 303-926-3000. Alternatively, SCP 214b can return a circuit identifier. SCP 214b usually returns a circuit identifier when the termination is a dedicated trunk to a customer premise equipment (CPE). Then if SCP 214b determines that it can not route the call or has determined to block the call (per the route plan), SCP 214b returns a ‘route to resource’ response to Soft-Switch 204 with an announcement identifier. In this case Soft-Switch 204 can connect the calling party with Announcement Server 246 for the playing of an announcement and then disconnect the caller.

[0695] SCP 214b can store call events in CDR database tables on SCP 214b. CDR database tables can then be replicated to Master Network Event Database 226 using a data distributor 222, such as, for example, the Oracle Replication Server.

[0696] The configuration server 206 will now be described in greater detail with reference to FIG. 2. Configuration server 206 supports transaction requests to a database containing information needed by network components. Configuration server 206 supports queries by voice network components during initialization and call processing. The data contained within configuration server 206 databases can be divided into two types. The first type of data is that used to initialize connections between components. Examples of such data used to initialize connections between network components include the following: IP address and port numbers for all servers that soft switch 204 must communicate with; information indicating initial primary/secondary/tertiary configurations for server relationships; configuration information for access gateways 238, 240 and trunking gateways 232, 234; number and configuration of bays, modules, lines and channels (BMLC); relationship of module, line and channels to originating point code (OPC), destination point code (DPC) and circuit identification code (CIC) values; relationship of module, line and channels to trunk groups; call processing decision trees for soft switch processing; mapping of OPC, DPC and CIC values soft switches 204; mapping of access server 254, 256 ports to dedicated access line (DAL) identifiers and customer IDs; tables necessary to support class of service (COS) restrictions; local access transport area (LATA) tables; state tables; and blocked country code tables.

[0697] The second set of data can be categorized as that data needed by soft switch 204 for use during call processing. This type of data includes customer and DAL profiles. These profiles define the services that a customer has associated with their ANIs or DALs. This information can include information describing class of service restrictions and account code settings.

[0698] The database of configuration server 206 contains voice network topology information as well as basic data tables necessary for soft switch 204 call processing logic. Configuration server 206 is queried by soft switches 204 at start-up and upon changes to this information in order to set up the initial connections between elements of telecommunications network 200. Configuration server 206 is also queried by soft switches 204 in order to configure initial settings within soft switch 204.

[0699] Configuration server 206 contains the following types of information: IP address and port numbers for all servers that soft switch 204 must communicate with; information indicating initial primary/secondary/tertiary configurations for server relationships; configuration information for AGs 238, 240 and TGs 232, 234; call processing decision trees for soft switch 204 call processing; mapping of OPC, DPC and CIC values to soft switch 204; mapping of access server 254, 256 ports to DALs and customer IDs; and tables necessary to support COS restrictions.

[0700] Configuration information for AGs and TGs includes: number and configuration of bays, modules, lines and channels; relationship of modules, line and channels to OPC, DPC and CIC values; and relationship of module, line and channels to trunk groups.

[0701] Tables necessary to support class of service restrictions include: LATA tables; state tables; and blocked country code tables.

[0702] Configuration server 206 also contains information related to customer trigger plans and service options. Customer trigger plans provide call processing logic used in connecting a call. Configuration server 206 information is queried during call processing to identify the service logic to be executed for each call.

[0703] The information that soft switch 204 uses to look-up customer profile data is the ANI, trunk ID or destination number for the call. The information that will be returned defines the call processing logic that is associated with ANI, trunk ID or destination number or trunk group.

[0704] Table 12 includes an example of a customer profile query.

[0705]

TABLE 12
Customer Profile Query
Customer Profile Query Field	Value
Customer identification type	DDD, DAL ID, Customer ID
Customer identification	The value for the DDD, Trunk ID

[0706] Table 13 includes an example of a customer profile query response provided by configuration server 206.

[0707]

TABLE 13
Customer Profile Query Response
Customer Profile Response Field	Value
Customer identification type	DDD, Trunk ID
Customer Identification	The value for the DDD, Trunk ID
Class of Service restriction Type	None
	Intrastate
	IntraLATA
	Domestic
	Domestic and selected international

[0708]

TABLE 13
Customer Profile Query Response
Customer Profile Response Field	Value
Selected International List ID	When the class of service
	restriction type is domestic
	and selected international
	destinations, this is an index
	to the list of allowed
	international destinations.
Account Code Type	None
	Verified Forced
	Unverified Forced
	Unverified Unforced
	Partially Verified Forced
Account code length	2-12 digits
Local Service Area, State, LATA,	For queries on numbers, these
and Country	fields are identify the
	geographic information that is
	necessary to process the call.

[0709] Configuration server 206 interfaces to components. Configuration server 206 receives provisioning and reference data updates from data distributor 222 of provisioning component 222. Configuration server 206 also provides data to soft switch 204 for call processing. Configuration server 206 is used by soft switch 204 to retrieve information necessary for initialization and call processing. Information that soft switch 204 retrieves from configuration server 206 during a query is primarily oriented towards customer service provisioning and gateway site 108, 110 port configuration. Configuration server 206 database tables accessible to soft switch 204 include the following: toll free number to SCP type translation; SCP type to SCP translation; CICs profiles; ANI profiles summary; ANI profiles; account code profiles; NPA/NXX; customer profiles; customer location profiles; equipment service profiles; trunk group service profile summaries; trunk group services; high risk countries; and selected international destinations.

[0710] Configuration server 206 uses a separate physical interface for all SNMP messages and additional functions that may be defined. Examples of additional functions that may be defined include provisioning, updating, and the passage of special alarms and performance parameters to configuration server 206 from the NOC.

[0711] In an alternative embodiment, the functionality of configuration server 206 can be combined with that of route server 212 in a single network component. In an additional embodiment of the invention, the functions of either or both of CS 206 and RS 212 can be performed by application logic residing on soft switch 204.

[0712] FIG. 8A depicts route server support for an exemplary soft switch site 800. FIG. 8A includes route server 212a and route server 212b. Route servers 212a and 212b are connected via redundant connections to soft switches 204a, 204b and 204c. Soft switches 204a, 204b and 204c are in turn connected to gateway sites via data network 112 (not shown). For example, soft switch 204a is in communication with TG 232a and TG 232b. Similarly soft switch 204b is in communication with AG 238a and TG 234a. Soft switch 204c is in turn in communication with AG 238b and AG 240a. It would be apparent to a person skilled in the art that additional TGs and AGs, as well as other gateway site devices, (such as a NAS device) can also be in communication with soft switches 204a, 204b and 204c.

[0713] Route server 212 will now be described in further detail with reference to FIG. 2. Route server 212 provides at least two functions. Route server 212 performs the function of supporting the logic for routing calls based upon a phone number. This routing, performed by route server 212, results in the selection of one or more circuit groups for termination.

[0714] Another function of route server 212 is the tracking and allocation of network ports. As shown in FIG. 8A, route server 212 (collocated with other components at soft switch site 104) services routing requests for all soft switches 204a, 204b, 204c at that site. Therefore, route server 212 tracks port resources for all TGs 232a, 232b and 234a and AGs 238a, 238b and 240a that are serviced by soft switches 204a, 204b and 204c at soft switch site 104.

[0715] The routing logic accepts translated phone numbers and uses anywhere from full digit routing to NPA-based routing to identify a terminating circuit group. Routing logic selects the translation based upon the best match of digits in the routing tables. An exemplary routing table is illustrated as Table 14.

[0716]

TABLE 14
Number Routing Table
		Terminating
	Number	Circuit Group	Priority	Load
	303-926-3000	34	1	50%
	303-926-3000	56	1	50%
	303-926-3000	23	2
	303-926	76	1
	303	236	1
	44 1784 470 330	564	1
	44	923	1

[0717] In Table 14, there are five entries that can match the dialed number “303-926-3000”. The first route choice is the one that has a full match of digits with priority one. Since there are two entries with full matching digits, and which are marked as priority one, the load should be distributed as shown in the load column, (i.e., 50% load share is distributed to the first, and 50% load share is distributed to the second). The second route choice is the entry with a full digit match, but marked with the lower priority of two. The third route match is the one that has a matching NPA-NXX. The last route choice is the one that has a matching NPA only.

[0718] In situations where there are multiple route choices for a DDD number (i.e., the number of called party 120) route server 212 must take into consideration several factors when selecting a terminating circuit group. The factors to be considered in selecting a terminating circuit group include: (1) the percent loading of circuit groups as shown in the load column of Table 14; (2) the throttling use of trunk groups to avoid overloaded networks; (3) the fact that end office trunk groups should be selected before tandem office trunk groups; and (4) routing based upon negotiated off-network carrier agreements.

[0719] Agreements should be negotiated with off-network carriers to provide the flexibility to route calls based upon benefits of one agreement another. The following types of agreements can be accounted for: (1) commitments for the number of minutes given to a carrier per month or per year; (2) the agreement that for specific NPA or NPA-NXX sets, one carrier may be preferred over another; (3) the agreement that international calls to specific countries may have preferred carriers; (4) the agreement that intra-LATA or intra-state calls originating for certain areas may have a preferred carrier in that area; and (5) the agreement that extended area service calls may have a preferred carrier.

[0720] The logic for route server 212 can include routing for international calls. In the example shown in Table 14, it is possible to have fully specified international numbers, or simply specified routing, for calls going to a particular country. As with domestic numbers, the routing logic should select the table entry that matches the most digits within the dialed number, (i.e. the number of called party 120).

[0721] Once a terminating circuit group has been identified, route server 212 needs to allocate a terminating circuit within the trunk group. The selection of a terminating circuit is made by querying the port status table. Table 15A shows an exemplary port status table. The results of a query to port status Table 15A yields the location and allocation of a circuit. Route server 212 can use algorithms to select circuits within the trunk group. Each circuit group can be tagged with the selected algorithm that should be used when selecting circuits within that group.

[0722] Example algorithms to select circuits within the group include: (1) the most recently used circuit within a circuit group, (2) the least recently used circuit within a circuit group; (3) a circular search, keeping track of the last used circuit and selecting the next available circuit; (4) the random selection of an available circuit within a circuit group; and (5) a sequential search of circuits within a circuit group, selecting the lowest numbered available circuit. Table 15A illustrates the association between a circuit group and the selection algorithm that should be used to allocate ports from that group.

[0723]

TABLE 15A
Circuit Group Parameters
	Circuit group	Selection algorithm
	34	Random
	35	Least recently used

[0724]

TABLE 15B
Port Status
	Circuit group	Port	Status
	34	3-4-6-1	Avail
	34	3-4-6-2	In-use
	34	3-4-6-3	avail
	34	3-4-6-4	avail

[0725] Table 15B includes the circuit group (that a port is a member of), a port identifier, and the current status of that port. The port identifier shown in Table 15B assumes the type of port identification currently used in the IPDC protocol, where the port is represented by a bay, module, line and channel (BMLC). It would be apparent to persons skilled in the art that other methods of identifying a port can be used.

[0726] The function of route server 212 is to provide least cost routing information to soft switch 204, in order to route a call from calling party 102 to called party 120. In addition to providing routing information, route server 212 allocates ports for terminating calls on the least cost routes, e.g., allocating ports within TGs 232, 234. Route server pair 212 is located at each of soft switch sites 104, 106, 302 and services all soft switches 204a, 204b, 204c, 304a, 304b, 304c, 306a, 306b and 306c at that site. (Refer to FIG. 3.)

[0727] Route server 212 interacts with at least two other voice network components. Route server 212 interacts with configuration server 206. Configuration server 206 is used to retrieve initial information on route server 212 start-up to set up the initial routing tables in preparation for receiving requests from soft switches 204a, 204b and 204c, for example.

[0728] Route server 212 also interfaces with soft switch 204. Soft switch 204 can send route requests to route server 212 that contain either a phone number or a circuit group. Route server 212 can perform its least cost routing logic to first select a terminating circuit group for the call. Using that circuit group, route server 212 can then select and allocate a terminating circuit.

[0729] A description of the messages and model of interaction between route server 212 and soft switch 204 follows. Route server 212 is used by soft switch 204 to identify the possible network terminations for a call. Soft switch 204 passes a DDD number, an international DDD (IDDD) number, or a circuit group to route server 212 in a “route request” message. Using this information from soft switch 204, route server 212 can return the port on an AG 238, 240 or TG 232, 234 that should be used to terminate this call. Using this port information, soft switch 204 can then signal the originating and terminating TG or AG to connect the call through data network 112.

[0730] The route server 212 will now be described further with reference to FIG. 2B. FIG. 2B depicts a sample call flow 258, illustrating how soft switch 204 interacts with route server 212 to identify a terminating port for a call.

[0731] In exemplary call flow 258, the call originates and terminates at different sites, specifically, gateway sites 108, and 110. Since exemplary call flow 258 originates and terminates at different sites, the cooperation of the originating soft switch 204 and terminating soft switch 304 and route servers 212, 314, respectively to identify the terminating circuit. Portions of the call flow will now be described in greater detail.

[0732] As depicted in step 259, for calls arriving on SS7 signal trunks, soft switch 204 receives call arrival notifications in the form of LAM messages. Upon receipt of the IAM message from SS7 GW 208, soft switch 204 performs some initial digit analysis to determine the type of the call.

[0733] In step 260, for calls involving customer features, soft switch 204 can use the ANI of calling party 102 (i.e., the telephone number of calling party 102) to query a customer profile database in configuration server 206. This is done to identify the originating customer's feature set. Each customer's feature set is known as a “trigger plan” for origination of the call. A trigger plan can be thought of as a flowchart which branches based on certain triggering events dependent on the caller's identity. Customer trigger plans 290 reside in a customer profile on configuration server 206.

[0734] In step 262, the customer profile database of configuration server 206 returns the customer trigger plan 290 to soft switch 204. Soft switch 204 can perform any processing necessary to implement the customer's specified originating triggers.

[0735] Application logic in soft switch 204 can then generate a translated number or an identification of the terminating circuit group for this call. For example, in the case of an 800 call, a translation may be requested as in step 265 of an SCP 214. SCP 214 converts the 800 number into a normal number for termination, and in step 266 returns the number to soft switch 204.

[0736] In step 267, in order to translate the translated number or circuit group into an egress port, soft switch 204 makes a route request to route server 212. The routing logic uses the NPA-N-XXXX to identify the terminating circuit group. Upon identifying the terminating circuit group, the route logic queries a circuit group to soft switch mapping table in route logic 294 of route server 212, to identify the target soft switch that handles the identified termination. For example, the target soft switch may be soft switch 304. It is important to note that there can be multiple route choices, and therefore there can be multiple soft switches 204, 304 supporting a single route request.

[0737] In step 268, route server 212 responds to soft switch 204 with the terminating circuit group. In this example, the terminating circuit group is included in trunks connected to trunking gateway 234, which is serviced by a different soft switch (namely soft switch 304) than originating soft switch 204. Therefore, route server 212 responds with the terminating circuit group and identifies soft switch 304 as the soft switch that handles that terminating circuit group.

[0738] In step 269, originating soft switch 204 initiates the connection from the origination to the termination, by requesting a connection from the originating trunking gateway 232. Trunking gateway 232, upon receipt of the set-up request from soft switch 204, allocates internal resources in trunking gateway 232.

[0739] TG 232 manages its own ports. In an example embodiment, TG 232 uses real time protocol (RTP) over UDP, and RTP sessions, which are ports used to implement an RTP connection. In step 270, TG 232 returns to soft switch 204 the IP address and listed RTP port.

[0740] In step 274, originating soft switch 204 issues a call setup command to terminating soft switch 304. This is the command identified by route server 212.

[0741] In step 276, soft switch 304 queries route server 314 to determine the termination port for the call. Specifically, soft switch 304 queries port status 298 of route server 314. The query in step 276, “passes in” as a parameter the terminating circuit group.

[0742] In step 278, route server 314 allocates a termination port and returns the allocated termination port to terminating soft switch 304.

[0743] In step 280, terminating soft switch 304 instructs the identified end point (i.e., trunking gateway 234) to reserve resources, and to connect the call. Terminating soft switch 304 passes in an IP address and an RTP port corresponding to the port that was allocated by originating TG 232.

[0744] In step 282, terminating TG 234 returns the allocated resources for the call to soft switch 304. For voice over IP (VOIP) connections, this includes the listed port and IP address for the terminating TG 234.

[0745] In step 284, terminating soft switch 304 returns to originating soft switch 204 the IP address of TG 234.

[0746] In step 286, originating soft switch 204 communicates with originating TG 232 in order to inform originating TG 232 of the listed port that was allocated by terminating TG 234. At this point, originating TG 232 and terminating TG 234 have enough information to exchange full duplex information.

[0747] In step 288, originating TG 232 acknowledges the receipt of the communication from soft switch 304 to soft switch 204.

[0748] Table 16A shows fields that can be included in a route request sent from soft switch 204 to route server 212. The route request can contain either a DDD number or a circuit group that requires routing. The route request message can also contain information about the call, collected from the IAM message, that is necessary to perform routing of this call. The route request message can also contain information about the call, necessary to perform routing of the call, which is obtained from the processing of the call. For example, in the case of an 800 call, this information can be a translated number.

[0749]

TABLE 16A
Values for Route Request sent to the Route Server
OSCP Route Request Parameter	Route Server-Route Request Value
Message Type	Route Server Route Request
Call Reference	Unique call identifier
Requesting Soft Switch	Soft Switch ID
Bearer Capability	Voice, Data or Fax
Destination type	DDD or circuit group
Destination	Fully translated DDD (or IDDD)
	number or circuit group ID
Originating LATA	LATA from IAM or from DAL profile
Calling Number	ANI
Originating station type	II-digits from IAM or DAL profile
Collected Digits	Not Used for Route Server

[0750] Table 16B shows fields which can be included in a response corresponding to the route response, sent from route server 212 back to soft switch 204.

[0751] Alternatively, each route response can include one route termination, and multiple consecutive route terminations can be determined with multiple route request/response transactions.

[0752]

TABLE 16B
Values for Route Response sent from the Route Server
Customer Profile Query Field	Route Server-Route Response Value
Message Type	Route Server Route Response
Call Reference	Unique call identifier
Result code	Success/Fail
Number of responses	Number of responses sent from the route
	server
Destination circuit group - 1	Terminating circuit group for the first
	route
Destination circuit - 1	Terminating circuit allocated by the
	route server for the first route
Outpulse digits - 1	Outpulse digit format for selected
	circuit on the first route
Destination number - 1	Destination number for the first route
Destination Soft Switch - 1	Soft switch servicing the circuit group
	for the first route
Destination circuit group - N	Terminating circuit group for the Nth
	route
Destination circuit - N	Terminating circuit allocated by the
	route server for the Nth route
Outpulse digits - N	Outpulse digit format for selected
	circuit on the Nth route
Destination number - N	Destination number for the Nth route
Destination Soft Switch - N	Soft switch servicing the circuit
	group for the Nth route

[0753] The route response message can contain a plurality of route terminations for the DDD or circuit group that was passed in as a parameter to route server 212. For example, the route response message can include 1 to 5 route choices. Each of the route choices of the route response message can include various fields of information. For example, each route choice can include the following information: the circuit group, the circuit, the outpulse digits, the destination number and the destination soft switch 304. Alternatively, each route response can include one route termination and multiple consecutive route terminations can be determined with multiple route request/route response transactions.

[0754] In situations where the selected circuit group is managed by the same route server 212 that serviced the route request, the response for that route can contain all the information about the destination. This is possible because route server 212 can identify and allocate the circuit within the circuit group.

[0755] In situations where another route server 314 services the selected circuit group, the response for that route only contains the circuit group and the destination soft switch 304. Originating soft switch 204 can then make a request to terminating soft switch 304 to query the terminating route server 314 for a circuit within the identified circuit group. The terminating soft switch 304 can then control the termination of the call.

[0756] Referring back to FIG. 2A, regional network event collection points (RNECPs) 224 serve as collection points for real-time recorded call events that can be used by other systems. Soft switch 204 generates call data. This call data can be collected during call processing. Call data can also be generated by capturing events from other network elements. These network elements include internal soft switch site 104 components and external components. External components include SCPs 214, intelligent peripherals (IPs), AGs 238,240, TGs 232, 234, and signaling components, such as STPs 250,252, SSPs, and off switch SCPs.

[0757] Soft switch 204 provides call event data to RNECPs 224. Call data can be collected by a primary and secondary server at each RNECP 224, using high availability redundancy to minimize the possibility of potential data loss. Data from RNECPs 224 can then be transmitted in real-time to a centralized server, called the master network event database (MNEDB) 226. The MNEDB is discussed further below, with reference to FIG. 20.

[0758] FIG. 9 depicts a network event collection architecture 900. FIG. 9 includes western soft switch site 104, central soft switch site 106 and eastern soft switch site 302. Soft switch sites 104, 106, 302 are illustrated as including RNE CPs for collecting events and routing events to a master database. Specifically, western soft switch site 104 has soft switches 204a, 204b, 204c communicating via a local area network to RNECPs 224a, 224b. RNECPs can include disks 914, 916. RNECPs 224a, 224b can be in direct communication with, as well as can take a primary and a secondary role in communicating with, soft switches 204a, 204b, 204c.

[0759] RNECPs 224a, 224b can route network events through management virtual private network (VPN) 910 to master network event data center 912. Network events come through management VPN 910 and can be routed via redundant paths to MNEDB server 226a and/or MNEDB 226b. MNEDBs 226a and 226b can communicate with one another. MNEDB 226a uses disks 926a as primary storage for its database. MNEDB 226a also uses disks 926b for secondary storage. Similarly MNEDB 226b uses primary and secondary disks, 926a, 926b.

[0760] MNEDB 226a and MNEDB 226b can be collocated or can be geographically diverse. Thus master data center 912 can be either in one geographical area or in multiple locations.

[0761] Management VPN 910 also collects events from the other soft switch sites, i.e., central soft switch site 106 and eastern soft switch site 302. Central soft switch site 106 includes soft switches 304a, 304b, 304c redundantly connected via a LAN to RNECPs 902 and 904. RNECP 902 has disks 918 and 920.

[0762] Eastern soft switch site 302 includes soft switches 306a, 306b, 306c, redundantly connected via a LAN. RNECPs 906 and 908 RNECP 906 can have disks 922 and 924.

[0763] RNECPs 902 and 904 of central soft switch site 106 and RNECPs 906 and 908 of eastern soft switch site 302 can route network events for storage in disks 926a, 926b of MNEDBs 226a, 226b.

[0764] This is done by routing network events via management VPN 910 to master data center 912. The soft switches generate event blocks and push event block data to the RNECPs. (Event blocks are recorded call events that are created during call processing.)

[0765] Each RNECP 224a, 224b, 902, 904, 906 and 908 forwards collected event blocks (EBs) to (MNEDBs) 226a, 226b, which are centralized databases. RNECPs 224a, 224b, 902, 904, 906 and 908 use separate physical interfaces for all SNMP messages and additional functions that may be defined. Additional functions that can be defined include provisioning, updating, and passing special alarm and/or performance parameters to RNECPs from the network operation center (NOC).

[0766] RNECPs 224a, 224b, 902, 904, 906 and 908 are used by soft switches 204a, 204b, 204c, 304a, 304b, 304c, 306a, 306b and 306c to collect generated call events for use in such services as preparation of billing and reporting. At specific points throughout the duration of a call, soft switches 204a, 204b, 204c, 304a, 304b, 304c, 306a, 306b and 306c take the information that the soft switches have collected during call processing and push that data to the RNECPs.

[0767] Multiple types of data are logged by the soft switches during call processing of a normal one plus (1+) long distance call using account codes. Examples of data logged by an exemplary soft switch 204 include: a call origination record on the originating side, call termination information on the terminating side, an account code record, egress routing information, answer information on the originating side, call disconnect information on the originating side, call disconnect information on the terminating side, and final event blocks with call statistics.

[0768] Exemplary soft switch 204 can record data during call processing. Soft switch 204 transfers call events from RNECP 224 to MNEDB 226 for storage. This call event data, stored in MNEDB 226, can be used by various downstream systems for post-processing. These systems include, for example, mediation, end-user billing, carrier access billing services (CABS), fraud detection/prevention, capacity management and marketing.

[0769] There are at least two types of EBs. Example Mandatory and Augmenting event blocks can be explained as follows.

[0770] Mandatory EBs are created by soft switch 204 during the initial point-in-call analysis. Initial point-in-call analysis includes going off-hook, (picking up the telephone set) call <insert> setup, initial digit analysis (i.e., digit analysis prior to any external database transactions or route determinations).

[0771] Since other events such as, for example, session/call answer, and SCP transactions, can occur during call processing, soft switch 204 can create augmenting EBs. Augmenting EBs are EBs which can augment the information found in a mandatory EB. Events such as, for example, route determination, and answer indication, can be recorded in an augmenting EBs.

[0772] Examples of mandatory and augmenting EBs follow. For a complete illustration of these EBs, the reader is referred to Tables 20-143 and the corresponding discussions below. Specifically, Tables 20-48 provide mandatory EBs, Tables 49-60 provide augmenting EBs, and Tables 61-143 provide the call event elements that comprise the Ebs.

[0773] The following event blocks are examples of Mandatory Event Blocks:

• • [0774] EB 0001—Domestic Toll (TG Origination);
  • [0775] EB 0002—Domestic Toll (TG Termination);
  • [0776] EB 0003—Domestic Toll (AG Origination);
  • [0777] EB 0004—Domestic Toll (AG Termination);
  • [0778] EB 0005—Local (TG Origination);
  • [0779] EB 0006—Local (TG Termination);
  • [0780] EB 0007—Local (AG Origination);
  • [0781] EB 0008—Local (AG Termination);
  • [0782] EB 0009—8XX/Toll-Free (TG Origination);
  • [0783] EB 0010—8XX/Toll-Free (TG Termination);
  • [0784] EB 0011—8XX/Toll-Free (AG Origination);
  • [0785] EB 0012—8XX/Toll Free (AG Termination);
  • [0786] EB 0013—Domestic Operator Services (TG Termination);
  • [0787] EB 0014—Domestic Operator Services (AG Origination);
  • [0788] EB 0015—Domestic Operator Services (OSP Termination);
  • [0789] EB 0016—International Operator Services (TG Origination);
  • [0790] EB 0017—International Operator Services (AG Origination);
  • [0791] EB 0018—International Operator Services (OSP Termination);
  • [0792] EB 0019—Directory Assistance/555-1212 (TG Origination);
  • [0793] EB 0020—Directory Assistance/555-1212 (AG Origination);
  • [0794] EB 0021—Directory Assistance/555-1212 (DASP Termination);
  • [0795] EB 0022—OSP/DASP Extended Calls (Domestic);
  • [0796] EB 0023—OSP/DASP Extended Calls (International);
  • [0797] EB 0024—International Toll (TG Origination);
  • [0798] EB 0025—International Toll (AG Origination);
  • [0799] EB 0026—International Toll (TG Termination);
  • [0800] EB 0027—International Toll (AG Termination);
  • [0801] EB 0040—IP Origination; and
  • [0802] EB 0041—IP Termination.

[0803] The following event blocks are examples of Augmenting Event Blocks:

• • [0804] EB 0050—Final Event Block;
  • [0805] EB 0051—Answer Indication;
  • [0806] EB 0052—Ingress Trunking Disconnect Information;
  • [0807] EB 0053—Egress Trunking Disconnect Information;
  • [0808] EB 0054—Basic 8XX/Toll-Free SCP Transaction Information;
  • [0809] EB 0055—Calling Party (Ported) Information;
  • [0810] EB 0056—Called Party (Ported) Information;
  • [0811] EB 0057—Egress Routing Information (TG Termination);
  • [0812] EB 0058—Routing Congestion Information;
  • [0813] EB 0059—Account Code Information;
  • [0814] EB 0060—Egress Routing Information (AG Termination); and
  • [0815] EB 0061—Long Duration Call Information.

[0816] In an example embodiment, soft switch site 104 comprises a plurality of object oriented programs (OOPs) running on a computer. As apparent to those skilled in the art, soft switch site 104 can alternatively be written in any form of software.

[0817] OOPs can be described at a high level by defining object oriented programming classes. For example, in an embodiment of the present invention, soft switch 204 comprise an OOP written in an OOP language. Example languages include C++ and JAVA. An OOP model is enforced via fundamental mechanisms known as encapsulation, inheritance and polymorphism.

[0818] Encapsulation may be thought of as placing a wrapper around the software code and data of a program. The basis of encapsulation is a structure known as a class. An object is a single instance of a class. A class describes general attributes of that object. A class includes a set of data attributes plus a set of allowable operations (i.e., methods). The individual structure or data representation of a class is defined by a set of instance variables.

[0819] Inheritance is another feature of an OOP model. A class (called a subclass) may be derived from another class, (called a superclass) wherein the subclass inherits the data attributes and methods of the superclass. The subclass may specialize the superclass by adding code which overrides the data and/or methods of the superclass, or which adds new data attributes and methods.

[0820] Thus, inheritance represents a mechanism by which subclasses are more precisely specified. A new subclass includes all the behavior and specification of all of its ancestors. Inheritance is a major contributor to the increased programmer efficiency provided by the OOP. Inheritance makes it possible for developers to minimize the amount of new code they have to write to create applications. By providing the significant portion of the functionality needed for a particular task, classes on the inheritance hierarchy give the programmer a head start to program design and creation.

[0821] Polymorphism refers to having one object and many shapes. It allows a method to have multiple implementations selected based on the type of object passed into a method and location. Methods are passed information as parameters. These are parameters passed as both a method and an invocation of a method. Parameters represent the input values to a function that the method must perform. The parameters are a list of “typed” values which comprise the input data to a particular message. The OOP model may require that the types of the values be exactly matched in order for the message to be understood.

[0822] Object-oriented programming is comprised of software objects that interact and communicate with each other by sending one another messages. Software objects are often modeled from real-world objects.

[0823] Object-oriented programs of the present invention are hardware platform independent. Client computer 7008 in a preferred embodiment is a computer workstation, e.g., a Sun UltraSPARC Workstation, available from SUN Microsystems, Inc., of Palo Alto, Calif., running an operating system such as UNIX. Alternatively a system running on another operating system can be used, as would be apparent to those skilled in the art. Other exemplary operating systems include Windows/NT, Windows98, OS/2, Mac OS, and other UNIX-based operating systems. Exemplary UNIX-based operating systems include solaris, IRIX, LINUX, PUX and OSF. However, the invention is not limited to these platforms, and can be implemented on any appropriate computer systems or operating systems.

[0824] An exemplary computer system is shown in FIG. 70B. Other network components of telecommunications network 200, such as, for example, route server 212 and configuration server 206, can also be implemented using computer system 7008 shown in FIG. 70B. Computer system 7008 includes one or more processors 7012. Processor 7012 is connected to a communication bus 7014.

[0825] Client computer 7006 also includes a main memory 7016, preferably random access memory (RAM), and a secondary memory 7018. Secondary memory 7018 includes hard disk drive 7020 and/or a removable storage drive 7022. Removable storage drive 7022 reads from and/or writes to a removable storage unit 7024 in a well known manner. Removable storage unit 7024 can be a floppy diskette drive, a magnetic tape drive or a compact disk drive. Removable storage unit 7024 includes any computer usable storage medium having stored therein computer software and/or data, such as an object's methods and data.

[0826] Client computer 7008 has one or more input devices, including but not limited to a mouse 7026 (or other pointing device such as a digitizer), a keyboard 7028, or any other data entry device.

[0827] Computer programs (also called computer control logic), including object oriented computer programs, are stored in main memory 7016 and/or the secondary memory 7018 and/or removable storage units 7024. Computer programs can also be called computer program products. Such computer programs, when executed, enable computer system 7008 to perform the features of the present invention as discussed herein. In particular, the computer programs, when executed, enable the processor 7012 to perform the features of the present invention. Accordingly, such computer programs represent controllers of computer system 7008.

[0828] In another embodiment, the invention is directed to a computer program product comprising a computer readable medium having control logic (computer software) stored therein. The control logic, when executed by processor 7012, causes processor 7012 to perform the functions of the invention as described herein.

[0829] In yet another embodiment, the invention is implemented primarily in hardware using, for example, one or more state machines. Implementation of these state machines so as to perform the functions described herein will be apparent to persons skilled in the relevant arts.

[0830] Prior to describing the class definitions in detail, a description of an exemplary software object in an OOP environment is described.

[0831] FIG. 70A is a graphical representation of a software object 7002. Software object 7002 is comprised of methods and variables. For example software object 7002 includes methods 1-8 7004 and variables V_I-V_N 7006. Methods 7004 are software procedures that, when executed, cause software objects variables 7006 to be manipulated (as needed) to reflect the effects of actions of software object 7002. The performance of software object 7002 is expressed by its methods 7004. The knowledge of software object 7002 is expressed by its variables 7006.

[0832] In object oriented programming, software objects 7002 are outgrowths (or instances) of a particular class. A class defines methods 7004 and variables 7006 that are included in a particular type of software object 7002. Software objects 7002 that belong to a class are called instances of the class. A software object 7002 belonging to a particular class will contain specific values for the variables contained in the class. For example, a software class of vehicles may contain objects that define a truck, a car, a trailer and a motorcycle.

[0833] In object oriented programming, classes are arranged in a hierarchical structure. Objects that are defined as special cases of a more general class automatically inherit the method and variable definitions of the general class. As noted, the general class is referred to as the superclass. The special case of the general class is referred to as the subclass of the general class. In the above example, vehicles is the general class and is, therefore, referred to as the superclass. The objects (i.e. truck, car, trailer, and motorcycle) are all special cases of the general class, and are therefore referred to as subclasses of the vehicle class.

[0834] Example OOP class definitions are now described. The functions performed by the methods included in the class definitions, and the type of information stored in and/or passed as parameters in the variables of the classes depicted, will be apparent to those skilled in the art.

[0835] FIG. 4B depicts a soft switch OOP class 418. Soft switch class 418 may be instantiated to create a soft switch application object. Related OOP classes will be described with reference to FIGS. 4C, 4D and 4E.

[0836] Soft switch class 418 includes variables 420 and methods 422. Variables 420 include information about a soft switch 204, including soft switch 204's identifier (ID), error message information, RNECP information, alarm server information, and run time parameters. Variables 420 can be used to provide information to the methods 422 included in soft switch class 418.

[0837] Methods 422 can include a method to start a soft switch to receive information, to receive a message, to receive a response to a message, and to perform updates. Methods 422 also include the means to read configuration data, to acknowledge messages, to get call context information from a signaling message, and to get call context information from an IPDC message. Methods 422 also include the means to get call context information from a route response, to get call context information from a route server message, and to forward messages.

[0838] FIG. 4B includes SS7 gateway proxy 424 which can have inter-object communication with soft switch class 418. FIG. 4B also includes route server proxy 426 and configuration server proxy 428, which can also have inter-object communication. These proxies can also be instantiated by soft switch class 418 objects.

[0839] FIG. 4B also includes route response 430, signaling message 432, and IPDC message 434, which can be passed parameters from soft switch class 418.

[0840] FIG. 4F depicts a block diagram 401 of interprocess communication including the starting of a soft switch command and control functions by a network operations center. Diagram 401 illustrates intercommunications between network operations center (NOC) 2114, soft switch 204 and configuration server (CS) 206. NOC 2114 communicates 404 with soft switch 418 to startup soft switch command and control. Soft switch command and control startup registers 405 soft switch 204 with CS 206 by communicating 411 with CS proxy 702, and accepts configuration information for soft switch 204 from CS 206.

[0841] FIG. 4G depicts a block diagram of soft switch command and control startup by a network operations center sequencing diagram 413, including message flows 415, 417, 419, 421 and 423.

[0842] FIG. 4H depicts a block diagram of soft switch command and control registration with configuration server sequencing diagram 425, including message flows 427, 429, 431 and 433.

[0843] FIG. 4I depicts a block diagram of soft switch accepting configuration information from configuration server sequencing diagram 435, including message flows 437, 439, 441, 443, 445 and 447.

[0844] FIG. 4C illustrates a call context class 438 OOP class definition. Call context class 438 includes variables 440 and methods 442.

[0845] Variables 440 can be used to store information about call context class objects 438. For example, variables 440 can include signaling message information for an incoming message, signaling message information for an outgoing message, a time stamp, and the number of stored signaling messages.

[0846] Methods 442 include various functions which can be performed by call context class 438. For example, methods 442 include a call context message which passes parameters identifying a call event and a signaling message. Other methods 442 include a function to get an IAM message, to get a call event identifier, to get an originating network ID, to get a terminating network ID, to get a signaling message, and to get a subroute. Methods 442 also include the means to add an ACM message, an ANM message, an REL message, an RLC message, a connect message, and a route response message. Methods 442 also permit call context class 438 to set various states as, for example, that an ACM was sent, an IAM was received, an RTP connect was sent, a CONI was received, a connect was sent, an answer was sent, an REL was sent, that the system is idle, that an ANM was sent, or that an RLC was sent. Methods 442 can also get a route.

[0847] FIG. 4C also includes route response 430, call context repository 444, call event identifier 448, and network ID 452. Call context repository 444 includes methods 446. Methods 446 include a register function, a function to get call context, and to find call context. Call event identifier 448 includes the function of identifying a call event 450.

[0848] FIG. 4D includes signaling message class 432 OOP class definition. Signaling message class 432 includes variables 456 and methods 458. Variables 456 include an originating message and a type of the message.

[0849] Classes 481 inherit from classes 432, i.e. class 432 is the base class for SS7 signaling messages.

[0850] Methods 458 include various signaling message functions which can pass various parameters and receive various parameters. Parameters which can be sent by signaling message functions include the request/response header (Rhs), the signaling message, the network ID, the port, the route response, the IPDC message and the soft switch information. Methods 458 also include the function to set the originating ingress port, to set the network identifier, to get a message type, and to get a network identifier.

[0851] FIG. 4D also includes network ID 452 and route response 430. Network ID 452 can communicate with signal message class objects 432. Route response 430 can receive parameters passed by signaling message class objects 432. FIG. 4D also includes ACK message 460, IAM message 464, ACM message 468, ANM message 472, REL message 476, and RLC message 480, collectively referred to as SS7 signaling message class definitions 481. Each message of SS7 message class definition 481 includes various functions. For example ACK message 460 includes methods 462, i.e., the ACK message function. LAM message 464 includes methods 466. Methods 466 include several functions, such as, for example the IAM message function, the get dialed digits function, the get NOA function and the get ANI function. ACM message 468 includes method 470, which includes function ACM message. ANM message 472 includes methods 474, which includes the ANM message function. REL message 476 includes methods 478, which includes the REL message functions. RLC message 486 includes methods 482, which includes the RLC message functions.

[0852] FIG. 5B includes SS7 gateway OOP class definition 532 and SS7 gateway proxy class definition 424. SS7 gateway class 532 includes variables 534, including runtime parameters, STP information, point code, and alias point code for an SS7 gateway.

[0853] FIG. 5C depicts a block diagram 536 of interprocess communication including soft switch interaction with SS7 gateways. Diagram 536 illustrates intercommunications between SS7 gateways (SS7 GW) 208 and soft switch 204. SS7 GW 208 communicates 538, 540 with soft switch 418. Soft switch 418 communicates 538 with SS7 GW proxy 424 accepting signaling messages from SS7 gateways 208. Soft switch 418 communicates 540 with SS7 GW proxy 424 sending signaling messages to SS7 gateway 208. In sending signaling messages, soft switch 204 uses 542 command and control registration of the soft switch 204 with SS7 gateway 208.

[0854] FIG. 5D depicts a block diagram 542 of interprocess communication including an access server signaling a soft switch to register with SS7 gateways. Diagram 542 illustrates intercommunications between access server 232a, soft switch 204 and SS7 gateway 208. Access server 232a communicates 544 with soft switch 418. Soft switch accepts IPDC messages from access servers from interaction with the servers. This communication extends 544 the soft switch command and control which registers soft switch 204 with SS7 gateways 232a. This registration uses 546 interaction between the soft switch and SS7 gateway 424. SS7 gateway 424 communicates 548 with the soft switch 418.

[0855] FIG. 5E depicts a block diagram of a soft switch registering with SS7 gateways sequencing diagram 550, including message flows 552-564.

[0856] FIG. 4E illustrates IPDC message OOP class definition 434. IPDC message 434 includes variables 484 and methods 486. Variables 484 include an IPDC identifier for an IPDC message. Methods 486 include IPDC message functions, which pass such parameters as the route node container, RHS, IPDC message, an IN port, an OUT port, and a bay module line channel (BMLC). Methods 486 include the get message type function, the get call event identifier function (i.e. passing the call event identifier variable), and the get IPDC identifier function (i.e., passing the IPDC identifier variable).

[0857] FIG. 4E includes call event identifier 448 in communication with IPDC message class 434, and route node container class 488 also in communication with IPDC message class 434 for passing parameters.

[0858] FIG. 4E also includes exemplary IPDC messages 495, which inherit from IPDC base class 434. IPDC messages 495 include ACR message 490, ACSI message 492, CONI connect message 494, connect message 496, RCR message 498, RTP connect message 454, and TDM cross connect message 497. IPDC messages can include various methods. For example, ACR message 490 can include ACR message function 493. Similarly connect message 496, RCR message 498, and RTP connect message 454, can include connect message function 491, RCR message function 489, RTP connect function methods, respectively.

[0859] FIG. 7A illustrates configuration server proxy OOP class definition 702. Configuration server proxy 702 includes methods 704. Methods 704 include multiple functions. For example, methods 704 include the register function, the get configuration data function, the update function, the update all function, and the get data function.

[0860] FIG. 7B depicts a block diagram 706 of interprocess communication including soft switch interaction with configuration server (CS) 206. Diagram 706 illustrates intercommunications between CS 206 and soft switch 204. CS 206 communicates 708, 710 with soft switch 418. Soft switch 418 communicates 708 with CS proxy 702 to register soft switch 204 with CS. Soft switch 418 communicates 710 with CS proxy 702 to permit soft switch 204 to accept configuration information from CS 206.

[0861] FIG. 8B depicts route server class diagram 802. Class diagram 802 includes route server OOP class definition 804. Route server class 804 includes variables 806 and methods 808.

[0862] Variables 806 include, for a respective route server 212, an identifier (ID), a ten digit table, a six digit table, a three digit table, a treatment table, a potential term table, an local serving area (LSA) table, a circuit group (CG) table, an destination AD table, a runtime parameters and an alarm server.

[0863] Methods 808 include several functions. For example methods 808 include a start function, a receive message function, a receive request function, an update function, a process function and a digit analysis function.

[0864] FIG. 8B includes route server proxy class 426.

[0865] FIG. 8B also includes route request class 430, from route objects superclass 803, which is passed parameters from route server class 804.

[0866] FIG. 8B also includes route server message class 810, also from route objects superclass 803, similarly receiving parameters from route server class 804.

[0867] FIG. 8B also includes configuration server proxy class 428, which is in communication with route server class 804.

[0868] FIG. 8B also includes RTP pool class 812, chain pool class 814 and modem pool class 818, all of which are from superclass pools 805, and are in communication with route server class 804. Circuit pool class 816, which is also from a superclass 805, is also in communication with route server class 804.

[0869] FIG. 8C illustrates superclass route objects 803 in greater detail. FIG. 8C includes route response OOP class definition 430. Route response class 430 includes variables 820 and methods 822.

[0870] Variables 820 include the type of a route response and a version of the route response. Methods 822 include several functions. For example, methods 822 include the route response function, the get type of route response function, the get call event identifier function, the get originating out BMLC function, the get originating IP function, the get terminating out BMLC function, the get terminating IP function, and the get terminating network ID function.

[0871] FIG. 8C includes route calculator class 824, including methods 826, which include a calculate function.

[0872] FIG. 8C includes route server message class 810, including methods 828. Methods 828 include several functions, including the route server message function, and the get BMLCs function.

[0873] FIG. 8C includes call event identifier class 448. Network call event identifier 448 is in communication with route response class 430.

[0874] FIG. 8C also depicts route request class 832 in communication with call event identifier class 448. Route request class 832 includes variables 834 and methods 836.

[0875] Variables 834 include the nature of address, the dialed digits, the ANI, version, and the jurisdiction information parameters, of route request class 832.

[0876] Methods 836 include multiple functions. Methods 836 include the route request function, the get dialed digits function, the get nature of address function, and the get network ID function. Network ID class 452 is in communication with route request class 832. Potential term container class 844 is in communication with route response class 430.

[0877] Route class 840 is in communication with route response class 430. Route class 840 includes methods 842. Methods 842 include several functions. For example methods 842 can include a route function, a get next function, a begin function, an end function, a get current function, an add route node function, and an end function. Route node class 846 is in communication with route class 840.

[0878] Route node 846 includes variables 848 and methods 850. Variables 848 include a BMLC, an IP, a location, and a bay name for a particular route node. Methods 850 include several functions. For example methods 850 can include a get OPC function, a get DPC function, a get terminating CIC (TCIC) function, a get IP function, a reserve function, a route node function, a get type function, a match function, a get pool function and a get BMLC function.

[0879] Call event identifier class 448 is in communication with route node class 846. Route node class 846 has additional route node subclasses 851. Route node subclasses 851 include MLC route node class 852, modem route node class 856, RTP route node class 858 and treatment route node class 862. MLC route node class 852 includes methods 854. Methods 854 includes several functions. For example methods 854 can include a match function, an are you available function, a get BMLC function and an unreserve function.

[0880] RTP route node class 858 includes methods 860. Methods 860 include several functions, e.g., a get address port pair function. Treatment route node class 862 includes variables 864, e.g., an announcement to play variable. RTP route node class 858 has two subclasses, i.e. IP address class 866 and IP port class 868.

[0881] Finally, FIG. 8C includes route node container class 488. Route node container class 488 includes methods 853. Methods 853 can include several functions, e.g., a begin function, a get current function, and a next function.

[0882] FIG. 8F depicts a block diagram 894 of interprocess communication including soft switch interaction with route server (RS) 212. Diagram 894 illustrates intercommunications between RS 212 and soft switch 204. RS 804 accepts 896 route requests from soft switch 418 and sends 898 route responses from RS 804 to soft switch 418. Soft switch manages ports by using RS 804 to process 899 unallocate messages from soft switch 418.

[0883] FIG. 8D depicts superclass pool class 870. Pool class 870 includes methods 872, including a get route node function and a find route node function. Pool class 870 has a plurality of subpool classes 871.

[0884] Subpool classes 871 include modem pool class 818, real-time transport protocol (RTP) pool class 812, and chain pool class 814. RTP pool class 812 includes methods 876.

[0885] Methods 876 include several functions, including a get originating route node function, a get terminating out route node function and a get route node function. Chain pool class 814 includes methods 878, including a get function, a get route node function, a get chain pair function and a get route node function. In communication with modem pool class 818 is modem route node class 856, which is a subclass from route objects 803. In communication with chain pool class 814 is chain pair class 874. Chain pair class 874 includes methods 880, including a match MLC route node function, a match function and an are you available function. Chain pair class 874 is in communication with MLC route node class 852, i.e., a subclass of route objects class 803.

[0886] FIG. 8E illustrates circuit pool class 816 having methods 886, including a get circuit function. In communication with circuit pool class 816 is a circuit class 882 having methods 888, including a get route node function. In communication with circuit class 882 is circuit group class 884 having variables 890 and methods 892. Variables 890 include a trunk group reference and a type for circuit groups of circuit group class 884. Methods 892 include an any available function. Method ID class 452 is in communication with circuit class 882. FIG. 8E also includes module line channel (MLC) route node class 852 from the route objects superclass.

[0887] FIG. 10A depicts a more detailed drawing 1000 of gateway site 108. FIG. 10A includes gateway site 108 comprising TG 232, NAS 228, AG 238, DACS 242 and announcement server ANS 246. TG 232, NAS 228 and AG 238 collectively are referred to as access server 254. DACs 242 could also be considered an access server 254 if it can be controlled by soft switch 204.

[0888] TG 232, NAS 228 and AG 238 are connected via an IP interface connection to data network 112. TG 232, NAS 228, AG 238 are connected via separate interface to network management component 118. Specifically, TG 232 is connected to network management component 118 via interface 1002. NAS 228 is connected to network management component 118 via interface 1004. Also, AG 238 is connected to network management component 118 via interface 1006.

[0889] In addition, FIG. 10A includes ANS 246, which as pictured is connected directly via the IP connection to data network 112. Alternatively, the ANS can functionally exist in other areas of the telecommunications network. For example, ANS 246 can functionality exist in TG 232, as depicted by ANS 1008, TG 232 having ANS functionality 1008. Similarly, ANS functionality (shown as ANS 1010) can be provided by AG 238.

[0890] FIG. 10A includes customer facility 128, providing access for calling party 122 to AG 238 via a direct access line or dedicated access line (e.g., a PRI or T1). In a preferred embodiment, signaling for calling party 122 is carried inband between customer facility 128 and AG 238 via a signaling channel, e.g., an integrated services digital network (ISDN) data channel (D-channel). Calling party 102, on the other hand, is connected via carrier-facility 126 to DACS 242, in order to provide connectivity to TG 232 and NAS 228. In a preferred embodiment, signaling for calling party 102 is carried out-of-band over signaling network 114, as shown in FIG. 10A.

[0891] FIG. 10B depicts a block diagram 1012 of interprocess communication including soft switch interaction with access servers such as trunking gateway 232a. Diagram 1012 illustrates intercommunications between access server 232a and soft switch 204. Soft switch 418 accepts 1014 IPDC messages from access server 232a. Soft switch 418 sends 1016 IPDC messages to access server 232a.

[0892] A TG is a gateway enabling termination of PSTN co-carrier trunks and feature group-D (FG-D) circuits. FIG. 11A illustrates an exemplary TG 232. Gateway common media processing is illustrated in FIGS. 11B and 11C below. Gateway common media processing on the ingress side will be described with reference to FIG. 11B. Gateway common media processing on the egress side will be described with reference to FIG. 11C.

[0893] Specifically, FIG. 11A depicts a trunking gateway high level functional architecture 1100 for TG 232. FIG. 11A includes calling party 102, connected via carrier facility 126 to DS3 trunks, which in turn provide connection to TG 232. Signaling for a call from calling party 102 is carried via out-of-band signaling network 114, through SS7 gateway 208, to soft switch 204. This is shown with signaling 1118.

[0894] TG 232 is controlled by soft switch 204, via the IPDC protocol 1116 through data network 112. TG 232 includes PSTN interface card 1102 connecting TG 232 to the incoming DS3 trunks from the PSTN. PSTN interface card 1102 is connected to a time division multiplexed (TDM) bus 1104.

[0895] TDM bus 1104 takes the incoming DS3 trunks and separates the trunks, using time division multiplexing, into separate DS1 signals 1106. DS1 1106 can be encoded/decoded via, for example, DSP-based encoder/decoder 1108. Encoder/decoder 1108 typically performs a voice compression, such as G.723.1, G.729, or simply breaks out G.711 64 kbps DS0 channels. Encoder/decoder 1108 is connected to packet bus 1110, for packetizing the incoming digital signals. Packet bus 1110, in turn, is connected to IP Interface cards 1112-1114. IP Interface cards 1112-1114 provide connectivity to data network 112 for transmission of VOIP packets to distant gateways and control messages to soft switch 204.

[0896] TG 232 also includes network management IP interface 1002 for receiving and sending network management alarms and events via the simple network management protocol (SNMP) to network management component 118.

[0897] Trunks can handle switched voice traffic and data traffic. For example, trunks can include digital signals DS1-DS4 transmitted over T1-T4 carriers. Table 17 provides typical carriers, along with their respective digital signals, number of channels, and bandwidth capacities.

[0898]

	TABLE 17
				Bandwidth in
		Number of	Designation	Megabits per
	Digital signal	channels	of carrier	second (Mbps)
	DS0	1	None	0.064
	DS1	24	T1	1.544
	DS2	96	T2	6.312
	DS3	672	T3	44.736
	DS4	4032	T4	274.176

[0899] Alternatively, trunks can include optical carriers (bCs), such as OC-1, OC-3, etc. Table 18 provides typical optical carriers, along with their respective synchronous transport signals (STSs), ITU designations, and bandwidth capacities.

[0900]

TABLE 18
	Electrical	International
	signal, or	Telecommuni-
	synchronous	cations Union	Bandwidth in
Optical carrier	transport signal	(ITU)	Megabits per
(OC) signal	(STS)	terminology	second (Mbps)
OC-1	STS-1		51.84
OC-3	STS-3	STM-1	155.52
OC-9	STS-9	STM-3	466.56
OC-12	STS-12	STM-4	622.08
OC-18	STS-18	STM-6	933.12
OC-24	STS-24	STM-8	1244.16
OC-36	STS-36	STM-12	1866.24
OC-48	STS-48	STM-16	2488.32

[0901] With reference to FIGS. 2A and 11A, TGs 232 and 234 can receive call control messages from and send messages to soft switch 204, via the IPDC protocol. Soft switch site 104 implements a signaling stack, e.g., an SS7 signaling network stack, for communications with legacy PSTN devices. On the ingress side of the telecommunications network, ingress trunking gateway 232 seizes a circuit as a call is initiated (i.e. assuming calling party 102 is placing a call to called party 120).

[0902] As the circuit is seized at call initiation, SS7 signaling network 114 begins the process of setting up a call, by sending messages via SS7 GW 208 to soft switch 204. As the call progresses, ingress TG 232 can receive commands from soft switch 204 to complete the call through ingress TG 232 and out through the virtual voice network via the IP interface 1114 to a destination gateway.

[0903] On the egress side of the network, this process is reversed to complete the call through the interconnected network to egress trunking gateway 234 and ultimately to called party 120.

[0904] FIG. 11B depicts gateway common media processing components on the ingress side 1140. FIG. 11B begins with incoming media stream 1142. From incoming media stream 1142, tone detection 1144 can occur and then data detection 1146 can occur or tone detection 1144 can be bypassed (see path 1148), as disabled/enabled by soft switch 204 via IPDC. From data detection 1146, silence detection/suppression 1150 can be performed. Next, a coder 1152 can be processed and then the packet stream can be transferred, as shown in 1154.

[0905] FIG. 11B is now described with respect to ingress trunking gateway 232. Incoming media stream 1142 must be processed as it passes through ingress gateway 232 to complete the call via the IP core data network 112.

[0906] The first process that takes place is data detection process 1146. Data detection process 1146 attempts to detect the media type of the call traffic. The media type of the call traffic can include voice, data and modem. The media type information can be passed via IPDC protocol to soft switch 204 for process determination.

[0907] In one embodiment, no additional processing is required. In another embodiment, a compression/decompression software component (CODEC) that is used in performing media processing, can be selected based on data detection process 1146. Specifically, if the data is determined to be modem traffic and if a suitable CODEC exists for the data rate, soft switch 204 can choose to incorporate this CODEC on the stream. Alternatively, if the call is a voice call, soft switch 204 can select the CODEC optimized for voice processing and current network conditions. In an embodiment of the invention, data calls can always be processed with the default bit rate CODEC.

[0908] In silence detection and suppression process 1150, silence in a voice call can be detected and suppressed, yielding potential decreases in the volume of transmission of packets carrying no digitized voice, due to silence.

[0909] In encoding process 1152, once a CODEC has been chosen by soft switch 204 or the decision is made to use the default CODEC, the media stream passes through a digital signal processor (DSP) 1108 to apply an appropriate compression algorithm. This compression processing algorithm can take the media stream as a traditional stream from the traditional voice world and transform it into a stream suitable for digital packetization. Once these packets have been formed, ingress TG 232 can process the packets into IP packets and prepare the packets for transport through the IP backbone 112 to egress TG 234.

[0910] On the egress side of the network, packetized media is converted back to a digital stream. Specifically, egress TG 234 can take the packets from data network 112 and decompress them and decode them with the same DSP process and algorithm used on the ingress side of the network.

[0911] FIG. 11C depicts exemplary gateway common media processing components on the egress side 1120. FIG. 11C begins with egress TG 234 receiving packets 1122. Next, packets are buffered to compensate for jitter 1124, and comfort noise 1126 can be inserted into the call. Comfort background noise process 1126 can provide reassurance to the party on the other end of the call that the call has not been interrupted, but instead that the other party is merely being silent. Next, decoding process 1128 can be performed by DSP 1108 and echo processing 1130 can detect and cancel echo. Finally, digital bit stream media, (e.g., a DS0), is transferred to a telephony interface (e.g., a DS3 port).

[0912] Additional media stream processing functions internal to TGs 232, 234 can include, for example, the ancillary processes of silence detection and suppression 1150, voice activation, and comfort noise insertion 1126. The media stream processing functions include, for example, the major core functionality needed for TGs 232, 234.

[0913] Other functional components needed in trunking gateways 232, 234 can also be included. Other functional components can include the provisioning and maintenance of trunking gateways 232, 234.

[0914] TGs 232, 234 provide voice network connectivity to the traditional public switched telephone network (PSTN). TGs 232, 234 can accept co-carrier and feature group-D (FG-D) trunks. It would be apparent to those skilled in the art that TGs 232, 234 can accept other telecommunications trunks. TGs 232, 234 allow for termination of SS7 signaled calls to and from telecommunications network 200.

[0915] TGs 232, 234 can convert the media stream into packets for transmission over data network 112. TGs 232, 234 also provide a management interface for remote management, control and configuration changes. TGs 232, 234 can interface to multiple components of telecommunications network 200. For example, TGs 232, 234 can interface with, for example, the PSTN for carrying media, soft switch 204 for communication of control messages from soft switch 204, the voice network interface of data network 112 for carrying packetized voice media, and network management component 118 for sending SNMP alerts to the network operation center (NOC).

[0916] TGs 232, 234 interface to the PSTN via co-carrier or FG-D trunks. These trunks are groomed via DACS 242, 244, to allow multiple two-way 64 kilobits per second (KPS) circuits to pass the media stream into and out of TGs 232, 234. The PSTN interface to TGs 232, 234 provides all low level hardware control for the individual circuits and allows the interface to look like another switch connection to the PSTN network.

[0917] TGs 232, 234 also interface with soft switch 204. Referring to FIG. 4A, the TG to soft switch interface 412 is used to pass information needed to control the multiple media streams. Soft switch 204 controls all available circuit channels that connect through TGs 232, 234. TG to soft switch interface 412 uses the physical IP network interface cards (NICs) 1112-1114 to send and receive control information to and from soft switch 204 using the IPDC protocol. The IPDC protocol will be described in greater detail below.

[0918] Referring to FIG. 11A, TGs 232, 234 interface with a voice virtual private network (VPN) that is overlaid on an IP data network 112. The TG to voice VPN interface sends or receives voice packets on the IP side of the network from TGs 232, 234 to other network components, e.g., to another of TGs 232, 234. TG to voice VPN interface, in a preferred embodiment, can physically be a 100 BaseT Ethernet interface, but can be logically divided into virtual ports that can be addressable via soft switch 204. The media stream can be connected through this interface, i.e., the TG to voice VPN interface, to a distant connection with a real-time transport protocol (RTP) connection.

[0919] TGs 232, 234 can also interface with network management component (NMC) 118 for the purposes of communicating network management SNMP alerts. The TGs 232, 234 to SNMP interface is a management interface that can be connected to NMC 118 of the network management network through a dedicated connection on TGs 232, 234. SNMP messages that are generated at TGs 232, 234 can be passed to the network operations center (NOC) through the TG to SNMP interface. In addition, messages and commands from the NOC can be passed to TGs 232, 234 through this interface for several purposes including, for example, network management, configuration and control.

[0920] An AG is a gateway that enables customers to connect via a Direct Access Line (DAL) from their customer premise equipment (CPE), such as, for example, a private branch exchange (PBX), to the telecommunications network. The AG terminates outgoing and incoming calls between the CPE, the telecommunications network and the PSTN.

[0921] FIG. 12 depicts an AG high level functional architecture 1200. FIG. 12 includes calling party 122, connected via customer facility 128 to DAL (e.g., either an ISDN PRI or a T1 DAL). A PRI DAL is connected from the PSTN-to-PSTN interface card 1202a. PSTN interface card 1202a includes ISDN signaling and media, meaning it includes both bearer channels (B-channels) for carrying media and data channels (D-channels) for carrying ISDN signaling information.

[0922] A T1 DAL can be connected from the PSTN to a PSTN interface card 1202b, supporting T1 in-band channel associated signaling (CAS). PSTN interface cards 1202a, 1202b are connected to TDM bus 1204. Using TDM bus 1204, incoming T1 and PRI signals are broken into separate DS1 signals 1206.

[0923] DS1 1206 is then encoded via DSP-based encode/decode 1208. After encoding via DSP-based encode/decode 1208, the signal is packetized via packet bus 1210, to be transmitted via IP interface cards 1212-1214, over data network 112. IP packets containing signaling information (e.g., D-channel) are routed to soft switch 204. IP packets containing media are transmitted to other media gateways, i.e. access servers such as an AG or TG

[0924] IP interface card 1214 includes both control and signaling information in its packets. This is illustrated showing IPDC protocol control information 1216 and signaling information 1218.

[0925] AG 238 delivers signaling information inband over data network 112 to soft switch 204. Accordingly, calling party 122 need not have its customer facility 128 have connectivity with SS7 signaling network 114.

[0926] AG 238 is functionally equivalent to TG 232. AG 238 differs from TG 232 only in the circuit types and scale of the terminated circuits supported. The circuit types and scale of terminated circuits supported drives the line side cards and signaling that AG 238 provides to a PBX or other customer facility 128. The circuit associated and in-band signaling provided by the PBX or customer facility 128 must be passed from AG 238 to soft switch 204 via the IPDC protocol. AG 238 receives call-processing information from soft switch 204.

[0927] AGs 238, 240 interface to several components of telecommunications network 200. The interfaces of AGs 238, 240 include interfaces facing the network, i.e., data network 112, and network management component 118, as described for TGs 232, 234 above. AGs 238, 240 also interface on the line side, through line side card interfaces, which can be needed to support in-band T1 and ISDN primary rate interface (ISDN PRI) circuits.

[0928] In-band T1 and ISDN PRI interfaces can be provisioned on an as-needed basis on AGs 238, 240, to support the equipment that can terminate the circuit on the far end. The ISDN PRI can support standard ISDN circuit associated D-channel signaling in the 23B+1D, NB+1D and NB+2D (bearer (B-) and data (D-) channel) configurations. For the in-band signaling T1 configuration, the circuit can support wink start or loop start signaling.

[0929] The next six paragraphs briefly introduce wink start, loop start, and ground start signaling as would be apparent to a person having ordinary skill in the relevant communications signaling art.

[0930] Wink start refers to seizing a circuit by using a short duration signal. The signal is typically of a 140 millisecond duration. The wink indicates the availability of an incoming register for receiving digital information from a calling switch. Wink starts are used in telephone systems which use address signaling.

[0931] Loop start refers to seizing a circuit using a supervisory signal. A loop start signal is typically generated by taking the phone off hook. With a loop start, a line is seized by bridging a tip and ring (i.e., the wires of the telephone line) through a resistance. A loop start trunk is the most common type of trunk found in residential installations. The ring lead is is connected to −48 V and the tip lead is connected to 0 V (i.e., connected to ground). To initiate a call, a “loop” ring can be formed through the telephone to the tip. A central office (CO) can ring a telephone by sending an AC voltage to the ringer within the telephone. When the telephone goes off-hook, the DC loop is formed. The CO detects the loop and the fact that it is drawing a DC current, and stops sending the ringing voltage.

[0932] Ground starting refers to seizing a trunk, where one side of a two-wire trunk (the ring conductor of the tip and ring) is temporarily grounded to get a dial tone. Ground starts are typically used for CO to PBX connections. Ground starting is effectively a handshaking routine that is performed by the CO and PBX. The CO and PBX agree to dedicate a path so that incoming and outgoing calls cannot conflict, so that “glare” cannot occur.

[0933] The PBX can check to see if a CO ground start trunk has been dedicated. In order to see if the trunk has been dedicated, the PBX checks to see if the tip lead is grounded. An undedicated ground start trunk has an open relay between 0 V (ground) and the tip lead connected to the PBX. If the trunk has been dedicated, the CO will close the relay and ground the tip lead.

[0934] In a ground start, the PBX can also indicate to the CO that it requires a trunk. The PBX has a PBX CO caller circuit. The PBX CO caller circuit can call a CO ground start trunk. The PBX CO caller circuit briefly grounds the ring lead causing DC current to flow. The CO detects the current flow and interprets it as a request for service from the PBX.

[0935] “Glare” occurs when both ends of a telephone line or trunk are seized at the same time for different purposes or by different users. Glare resolution refers to the ability of a system to ensure that if a trunk is seized by both ends simultaneously, then one caller is given priority, and the other is switched to another trunk.

[0936] AGs 238 and 240 interface to the PSTN via T1 CAS signaling and ISDN PRI trunks. ISDN PRI trunks are groomed via the DACS 242 and 244 to allow multiple two-way 64 kps circuits to pass signaling information circuits to pass signaling information and the media stream into and out of AGs 238 and 240. The AG to PSTN interface provides all low level hardware control for the individual circuits. The AG to PSTN interfaces, specifically, PSTN interface cards 1202a and 1202, also allow the interface to look like a switch connection to the PSTN network.

[0937] AG to soft switch interface 414 can be used to pass information needed to control multiple media streams. Soft switch 204 can control all available circuit channels that connect through AGs 238, 240. AG to soft switch interface 414 can use the physical voice network interface card to send and receive control information to and from soft switch 204 using the IPDC protocol.

[0938] AGs 238, 240 can have a separate physical interface to network management component (NMC) 118. AG 238 has network management IP interface 1006, which sends network management alarms and events in the SNMP protocol format to NMC 118. The AG to NMC interface can be used for delivery of SNMP messages and additional functions. Examples of additional functions that can be defined include, for example, functions for provisioning, updating, and passing special alarms and performance parameters to AGs 238, 240 from the network operation center (NOC) of NMC 118.

[0939] NASs 228, 230 accept control information from soft switch 204 and process the media stream accordingly. Modem traffic is routed to the internal processes within NASs 228, 230 to terminate the call and route the data traffic out to data network 112. The reader is directed to U.S. patent application entitled “System and Method for Bypassing Data from Egress Facilities”, filed concurrently herewith, 09/196,756, which is incorporated herein by reference in its entirety, describing with greater details the interaction between NASs 228, 230 and control server soft switch 204.

[0940] FIG. 13 depicts a NAS high-level architecture 1300. FIG. 13 includes calling party 102 calling into carrier facility 126. Its signaling information is routed via out-of-band signaling network 114 to SS7 GW 208. The signaling information 1318 is sent to soft switch 204.

[0941] NAS 228 receives trunk interfaces from the PSTN at PSTN interface card 1302. PSTN interface card 1302 is connected to TDM bus 1304.

[0942] TDM bus 1304, in turn, can break out separate DS1 signals 1306. These DS1 signals 1306 can be terminated to modems 1308. Modem 1308 can convert the incoming data stream from a first format to a second format over packet bus 1310 to IP interface card 1312 or 1314. It is important to note that IP interfaces 1312 and 1314 are the same.

[0943] Interface card 1312 carries media (e.g., data, voice traffic, etc.) over data network 112. The media can be sent over multiple routers in data network 112 to the media's final destination. IP interface card 1314 transmits packets of information through data network 112 to soft switch 204, including control information 1316 in the IPDC protocol format. Interface cards 1312 and 1314 can also perform additional functions

[0944] NAS 228 includes network management interface card (NMIC) 1004, for providing network management alarms and events in an SNMP protocol format to network management component 118.

[0945] Telecommunications network 200 supports interaction with NASs via communication of control information from soft switch 204. The interfaces between NASs 228, 230 and the other network components of telecommunications network 200, can be identical to those found on TGs 232, 234, with the exception of the FG-D interface.