A METHOD FOR INFORMING TYPE OF CALL SESSION CONTROL FUNCTION

摘要

A method for identifying CSCF(Call Session Control Function) types is provided to enable each server to identify which CSCF should be performed by expanding/defining SIP(Session Initiation Protocol) syntax. If registration process starts, a terminal transmits a registration message to the first server(S201). The first server judges whether a P(Proxy)-CSCF is executed. If the P-CSCF is executed, the first server adds "cscf=p-cscf" to the header(203). However, if the P-CSCF is not executed, the first server judges whether an I(Interrogating)-CSCF is executed(S204). If the I-CSCF is executed, the first server whether the passing of an INVITE message is required(S205). If the passing of the INVITE message is required, the first server adds "cscf=i-cscf" to the header(206). However, if the passing of the INVITE message is not required, the first server transmits the registration message to the next server(S209).