Patent ID: 8792483

Claim:
A method for rejecting received SIP (Session Initiation Protocol) messages which are redundantly retransmitted in a SIP application architecture, wherein the message type and transmission direction of said SIP messages are known, said method comprising the steps of; (a) forwarding all the messages transmitted from a SIP application server to a SIP terminal according to the transmission direction of said SIP messages; (b) determining whether the received SIP messages transmitted from the SIP terminal to the SIP application server are redundantly retransmitted based on the transmission direction of said SIP messages, dropping all the received SIP messages redundantly retransmitted from the SIP terminal to the SIP application server, and responding to the dropped SIP messages according to the message type thereof, if said received message transmitted from the SIP terminal to the SIP application server is redundantly retransmitted, then dropping said redundantly retransmitted message; performing transaction query on a received SIP message to find whether a transaction item containing transaction information corresponding to the received SIP message in a transaction table exists, wherein said transaction information includes transaction ID, message arrival time and a corresponding response related to the SIP message.