SIP gateway of backup methods and SIP gateway

摘要

PROBLEM TO BE SOLVED: To provide a technology of easily performing handover a data relay from its own repeater to other repeater.;SOLUTION: A primary gateway 1 regularly generates an executing signal including session information, and sends it to a secondary gateway 1. The secondary gateway 1 regularly receives the executing signal from the primary gateway 1, and when a given period of time has elapsed after having finally received the executing signal, the secondary gateway 1 sends a repeater address change request for notifying IP telephone terminals 2 and 6 specified by the session information stored in the finally received executing signal that an address of a gateway relaying a using session has changed from an address of the primary gateway 1 to an address of the secondary gateway 1.;COPYRIGHT: (C)2011,JPO&INPIT