Abstract: A routing system for implementing a service and topology exchange protocol (STEP) includes a primary STEP server configured to maintain a STEP repository and a plurality of routers, with each router including a STEP client in communication with the primary STEP server. The STEP client of each router is configured to transmit, using STEP, STEP documents containing service and topology state information for at least one route or service available through the router to the primary STEP server for storage in the STEP repository. The primary STEP server is configured to transmit to the STEP client of each router, using STEP, service and topology state information from the STEP repository for at least one other router based on configured relationships between routers. Each router is configured to make routing decisions based at least in part on the service and topology state information from the at least one other router.

Abstract: A router advertises an aggregated service or route that can be evaluated by other routers as a unitary segment rather than as a group of individual links/paths associated with the aggregated service or route. The aggregated service or route can be based on service and topology state information received from one or more other routers and can be advertised with the router as the nexthop for the aggregated service or route. The router can advertise an aggregated metric for the aggregated service or route for use in such evaluation. An aggregated route can be associated with different aggregated metrics for different services.

Abstract: A routing system for distributing multicast routing information for a multicast service includes a plurality of routers including a multicast source router and a plurality of multicast receiver routers, the plurality of routers providing a multicast service, wherein the routers are configured to exchange multicast information associated with the multicast service including identification of multicast sources and the multicast receivers.

Abstract: A packet routing method for directing packets of a session in an IP network causes an intermediate node to obtain a lead packet of a plurality of packets in a given session. The intermediate node has an electronic interface in communication with the IP network and obtains the lead packet through that same interface. The method maintains, in a routing database, state information relating to a plurality of sessions in the IP network. Each session includes a single stateful session path formed by an ordered plurality of nodes in the IP network, and the state information includes information about the ordered plurality of nodes in the sessions. The method further accesses the routing database to determine the state of a plurality of sessions, and forms a stateful given path for packets of the given session across the IP network as a function of the state information in the routing database.

Abstract: An intermediate node obtains a lead packet of a plurality of packets in a session having a unique session identifier, modifies the lead packet to identify at least the intermediate node, and then forwards the lead packet toward the destination node though an intermediate node electronic output interface to the IP network. The intermediate node also receives, through an intermediate node electronic input interface in communication with the IP network, a backward message from a next node having a next node identifier. The backward message includes the next node identifier and the session identifier. The intermediate node forms an association between the next node identifier and the session identifier, stores the association in memory to maintain state information for the session, and obtains (e.g., receives) additional packets of the session. Substantially all of the additional packets in the session are forwarded toward the next node using the stored association.

Abstract: A method and system are adapted to provide telephony services to aggregate endpoints on an Internet Protocol Multimedia Subsystem (IMS) network. The method includes assigning one or multiple PUIDs for surrogate registration purposes during the provisioning of the aggregate endpoint, performing reliable surrogate registration on behalf of the aggregate endpoint, allowing multiple SBCs to perform surrogate registrations independently for the same aggregate endpoint to achieve reliability, and providing reliable connection from an IMS core to the aggregate endpoints via multiple S/BCs. The system includes one or more Session Border Controllers (S/BC), at least one set of Call/Session Control Functions (CSCF), and an HSS operatively coupled together.

Abstract: A packet routing method for directing packets of a session in an IP network causes an intermediate node to obtain a lead packet of a plurality of packets in a given session. The intermediate node has an electronic interface in communication with the IP network and obtains the lead packet through that same interface. The method maintains, in a routing database, state information relating to a plurality of sessions in the IP network. Each session includes a single stateful session path formed by an ordered plurality of nodes in the IP network, and the state information includes information about the ordered plurality of nodes in the sessions. The method further accesses the routing database to determine the state of a plurality of sessions, and forms a stateful given path for packets of the given session across the IP network as a function of the state information in the routing database.

Abstract: An intermediate node obtains a lead packet of a plurality of packets in a session having a unique session identifier, modifies the lead packet to identify at least the intermediate node, and then forwards the lead packet toward the destination node though an intermediate node electronic output interface to the IP network. The intermediate node also receives, through an intermediate node electronic input interface in communication with the IP network, a backward message from a next node having a next node identifier. The backward message includes the next node identifier and the session identifier. The intermediate node forms an association between the next node identifier and the session identifier, stores the association in memory to maintain state information for the session, and obtains (e.g., receives) additional packets of the session. Substantially all of the additional packets in the session are forwarded toward the next node using the stored association.

Abstract: Systems and methods of establishing IP telephony sessions between enterprises are disclosed. A first enterprise requests an association with a second enterprise. Both enterprises and the second enterprise belong to the same federation. The association request is accepted, to establish an association between the first and second enterprises. In response to the acceptance, a direct routed path is established between the first enterprise and the second enterprise. One of the associated enterprises requests activation of an IP telephony service. If the request to activate references the association, an IP telephony session is established using the direct routed path.

Abstract: A method and system are adapted to provide telephony services to aggregate endpoints on an Internet Protocol Multimedia Subsystem (IMS) network. The method includes assigning one or multiple PUIDs for surrogate registration purposes during the provisioning of the aggregate endpoint, performing reliable surrogate registration on behalf of the aggregate endpoint, allowing multiple SBCs to perform surrogate registrations independently for the same aggregate endpoint to achieve reliability, and providing reliable connection from an IMS core to the aggregate endpoints via multiple S/BCs. The system includes one or more Session Border Controllers (S/BC), at least one set of Call/Session Control Functions (CSCF), and an HSS operatively coupled together.

Abstract: Systems and methods of establishing IP telephony sessions between enterprises are disclosed. A first enterprise requests an association with a second enterprise. Both enterprises and the second enterprise belong to the same federation. The association request is accepted, to establish an association between the first and second enterprises. In response to the acceptance, a direct routed path is established between the first enterprise and the second enterprise. One of the associated enterprises requests activation of an IP telephony service. If the request to activate references the association, an IP telephony session is established using the direct routed path.

Abstract: Methods and computer-readable media are provided to select the optimal route for communicating a signaling message in a telecommunications networking environment. The method includes receiving a signaling message at a sending proxy that is responsible for sending the signaling message to its destination. To determine the best route, the sending proxy inspect its dynamic routing table to identify one or more potential routes that can be used to communicate the signaling message to its destination. The optimal route is determined by a numeric value, which may be based on one or more of a cost, the relationship between service providers, quality, or the like. Once the optimal route is determined, it is communicated from the sending proxy to the receiving proxy, often through one or more intermediary proxies.