TELECOMMUNICATIONS NETWORK WITH RELOCATEABILITY OF SUBSCRIBER NUMBER

摘要

A telecommunications domain (20) having subscriber number relocateablity includes a plurality of physical nodes or exchanges (22) between which calls are connected and a subscriber location server (30) which is connected to and accessed by each of the plurality of exchanges (22) in the domain (20). Each exchange (22) has a unique exchange identifier (ID). Generally, when a call is placed to a subscriber in the relocateability domain, a first exchange the call encounters in the domain queries the subscriber location server. When queried, the subscriber location server (30) returns a Network Routing Number (NRN) which includes a Network Routing Prefix (NRP). The Network Routing Prefix (NRP) is a node identifier (NI) for the local exchange to which the called party is connected. The exchange (22) to which the NRN is returned prepares a routing message for the call by including the Network Routing Prefix (NRP) in an Address Signal Field (ASF) of a routing message and by setting a number relocateability flag (NRF) in the routing message. Using the NRP of the routing message, the call is routed to the called party exchange (i.e., the terminating exchange). In the called party exchange, the exchange identifier is recognized as its "own" and thereafter the rest of the Address Signal Field (ASF) is analyzed to identify the called subscriber line.