Abstract: In a tool for use by network planners in designing metropolitan IP aggregation networks, several optimization methods are integrated into a tool. A k-means algorithm is used to choose access packet switch locations. A dual-k-means algorithm is used to choose the backbone switch locations. Each access packet switch is dual homed to two backbone packet switches using two diverse paths. The diverse path configuration is found using a maxflow-mincost algorithm on a modified fiber map topology. The link topology connecting the backbone packet switches to each other is designed using a heuristic that creates a skeleton network topology and then adds express links one by one, testing each link to assure reduced overall network cost. The resulting network topology is then improved upon by local search.

Abstract: To facilitate routing changes, a telecommunications network (10, 10?, 10??) includes a centralized network routing database (28) queried by each ingress switch upon receipt of a call by a calling subscriber (12). In response to the query, the network routing database returns to the querying switch the identity on the next (downstream) switch in the routing path. The querying switch then translates the switch identity to establish the link to that next switch. Because each querying switch makes the necessary translation of the next switch identity to make the link to the next switch, the centralized network database need not concern itself with the particular characteristics of the switch. To make global routing changes, only the network routing database need be updated, not each individual switch.

Abstract: This invention provides a telecommunications routing system and method that allows a switch (e.g., an intelligent peripheral) to control the routing to a special applications device, which results in savings of time, cost and capacity throughout the entire network. Control of the routing lies within the Service Switching Point (SSP) which reduces the need to requery a Service Control Point (SCP) in error situations. This invention incorporates into the SSP a remote IP routing table containing routing instructions for IPs. The SSP will know if an alternate route is possible, based on the error from the IP. The SSP will have a rudimentary intelligence about routing which allows it to reroute when necessary, without requerying back to the SCP. The remote IP routing table will also allow the SSP to route to a successive IP if the local IP, although operative, cannot process the request.

Abstract: In an environment of competitive local and interexchange carriers, offering number portability between local carriers serving a common region and between switches serving that region, each local carrier accesses a regional database to determine the identity of the carrier and switch serving a local customer. In addition, interexchange carriers access a national database to determine the identity of the carrier and switch serving the customer specified by the number dialed by an originating customer. For customers requiring high reliability service, alternate carriers can be used to serve such customers in case the primary carrier is unavailable; the databases identify these alternate carriers. Advantageously, this arrangement allows a high degree of freedom of movement of customers between carriers and geographic relocation without requiring a number change.

Abstract: In accordance with the teachings of a prior application, in a telecommunications network, a local database stores destination telephone number information derived from a more global database, shared by a plurality of switching systems usually remote from all or most of the systems. One or more bit maps are used to store key indicators for each telephone number for which information may be required. This invention relates to a method and apparatus for automatically updating the local database, by recognizing that a switch identified as serving a directory number does not have access to the line corresponding to that number; when this condition is discovered, the global database is increased and the local database updated.

Abstract: In a telecommunications network, a method and apparatus for decreasing access time of information normally stored in a data base, shared by a plurality of switching systems usually remote from all or most of the systems. One or more bit maps are used to store key indicators for each telephone number for which information may be required. In one specific embodiment, a bit map indicates whether the information is stored locally in the switch, so that an access to the remote database is not required. In another embodiment, a bit map stores an indication of whether the desired information is a default attribute, or one of a plurality of common attributes of the information being sought. Advantageously, the number of data accesses required of the remote data base is sharply reduced, thus reducing the average call set up time.

Abstract: In an environment of competitive local and interexchange carriers, offering number portability between local carriers-serving a common region and between switches serving that region, each local carrier accesses a regional database to determine the identify of the carrier and switch serving a local customer. In addition, interexchange carriers access a national database to determine the identity of the carrier and switch serving the customer specified by the number dialed by an originating customer. For customers requiring high reliability service, alternate carriers can be used to serve such customers in case the primary carrier is unavailable; the databases identify these alternate carriers. Advantageously, this arrangement allows a high degree of freedom of movement of customers between carriers and geographic relocation without requiring a number change.