Processing of local number portability calls in a signal transfer point

摘要

In a telecommunications network (1), a signal transfer point (10) receives an Initial Address Message (IAM) generated by an originating service switching point (12) according to a call from an originating subscriber (20). The IAM includes a destination number associated with a destination subscriber (22). If the destination number has not been ported, the signal transfer point (10) sends a return message to the originating service switching point (12) indicating that no changes are to be made to the IAM. As a result, the originating service switching point (12) forwards the IAM to a destination service switching point (13) for processing of the call. If the destination number has been ported, the signal transfer point (10) performs a local number portability look-up in a database (24). The signal transfer point (10) obtains a redirection number from the database (24) for transfer in a return message to the originating service switching point (16). The originating service switching point (12) includes the redirection number in the IAM message transferred to the destination service switching point (13). <IMAGE>