SIP-BASED CALL/SESSION FORWARDING METHOD AND A SYSTEM, PARTICULARLY IN CONNECTION WITH FORWARDING A CALL ACCORDING TO EACH ORIGINATOR NUMBER OR TIME ZONE DURING A CALL SETUP PROCESS BASED ON AN SIP

摘要

PURPOSE: An SIP(Session Initiation Protocol)-based call/session forwarding method and a system are provided to forward a call requested by an originator to an address designated by a subscriber on the basis of an SIP, or to forward the call to the designated address at a previously designated time. CONSTITUTION: An SIP server 'A' services a terminal 'A'(S101). A position server 'B' supplies an address of an SIP server 'B' to the SIP server 'A'(S102). The SIP server 'A' sends an invite message to the SIP server 'B'(S103). The SIP server 'B' decides whether a terminal 'B' is registered in a call forwarding service(S104). An SIP AS recognizes that the call forwarding service is set, and decides that a call should be forwarded to a terminal 'C'(S105). The fact that the call is forwarded to a user may not be displayed(S106,S107,S108). An SIP application server generates a new invite message, and transmits the new invite message to the SIP server 'B'(S109). The SIP server 'B' analyzes a receiving number of the new invite message, and finds out an address of an SIP server 'C' while sending the invite message to the SIP server 'C'(S110,S111). The SIP server 'C confirms the terminal 'C' by analyzing the invite message, and routes to cause a final call receiving process in the terminal 'C'(S112).