Patent ID: 7787459
Filing Date: 2010-08-31
Classification: H04L

Abstract:
1. A method for implementing traversal through a Network Address Translation (NAT) server or a firewall (FW) located in a first network, the method comprising: recording a first address and port in an IP header of a signaling message of a call received from the NAT server or FW located in the first network; modifying the first address and port into a second address and port assigned by the proxy server for the call in the second network; analyzing the information in the signaling message; recording an address and port of a call signaling in a payload of the signaling message; and Recording an address and port of Real-time Transfer Protocol (RTP) and Real-time Transfer Control Protocol (RTCP) of a media stream in the signaling message; modifying the address and port of the call signaling into the address and port of the call signaling of the second network assigned by the proxy server for the call; modifying the address and port of RTP and RTCP into the address and port of the second network assigned by the proxy server for the media stream; delivering the signaling message to a processing device of packet voice signaling or a service processing device in the second network; modifying a third address and port in the IP header of a response signaling message from the processing device of packet voice signaling or the service processing device into the first address and port; analyzing the information in the response signaling message; modifying an address and port of a response signaling in a payload of the response signaling message into the recorded address and port of the call signaling in the payload of the signaling message; modifying a RTP and RTCP address and port of a media stream in the response signaling message into the recorded RTP and RTCP address and port of the media stream in the signaling message; and sending the response signaling message to the NAT server or FW in the first network, wherein the method is implemented in the proxy server located in the second network outside the NAT server or the FW.