Avoiding temporary loss of availability during porting of telephone number to different network operator

摘要

The subscriber receives a service number (SNa) from his present telecommunications network operator, to allow access to a number porting bridge implemented as a service station. Using a call relaying circuit (CFa) a call of the subscriber from the number affected by the porting, is routed to the service number (SNa) and the number porting bridge. The number porting bridge routes the incoming calls to the service number to the old network, or if possible, the new network.