The Research Of Key Technology Of SIP Internet Phone On P2P

With the development of Internet mode and popularization of the broadband access , Internet plays a key role in our lives and work. Internet phone ,as a new optional communication tool , gets more and more attracted ,for its high quality and low price ,also all kinds of added-value servie .SIP(Session Initiation Protocol), as the key protoco: in NGN and 3GGP-IMS(IP Multimedia Subsystem) , will get its place in the Network-combined process. It was borned with the well-extended and efficient characteristic ,when setting up the session . It will be the trend of the Internet Phone.Aslo, another technology attracts us: Peer-to-Peer. With P2P technology we can fully make use of the end-point increasing computing capacity , also it can get rid of some shortage of the C/S(Clinet/Server) mode, which is popular nowdays, such as not easy to extend the system, causing one point failure, lack of band during the hot access..This thesis focuses on a SIP phone system based on the P2P ,first itdesigns an architecture of the system ,then pays attention to the arithmetic of resource location,brings up a P2P resource location model---Hierarchical, high level Chord model which adapts for the WAN circumstance, also it puts up the simulation result of high level Chord model and analyses the result, the result really meets our expectation.In the end we extend SIP to carry the P2P message and have finished the antetype of the system based on oSIP.