Integration Of P2P And SIP & Design And Realization Of P2P-SIP Terminal

Along with the rapid development of network applications, Voice over IP technology has been applied widely, the support of SIP(Session-Initiate-Protocol) is the mainstream of IP communication service, the P2P(Peer-to-Peer) technology has gained great successes in file sharing, distributed calculation, distributed storage and so on. The rapid increase of users require that the center server in C/S(Client/Server) mode has stronger service capability, larger storage, better bandwidth, smaller delay of network and better security. These requirements make the cost of server higher, have the server blocked or crashed. To solve these problems, this paper conducts the research on integration of P2P SIP.First, the integration of P2P SIP is much necessary and important. In the case of none center server, DHT (Distributed-Hash-Table) algorithm has applied to P2P network widely. SIP has been a core protocol of VoIP technology, has great expansibility. The integration between P2P and SIP boosts up their characters. SIP using P2P and P2P based on SIP, are thought as the two solutions of integration between P2P and SIP.Then, the DHT algorithm of P2P is discussed. The DHT has four typical algorithms: Chord, CAN, Pastry and Tapestry, their advantages and disadvantages are listed. With the example of Chord, P2P SIP route algorithms are researched, including the procedures of discovery, insert, find, stability and leaving of nodes. Possible key technologies, which are the uniqueness of node's ID, multicast technology, Chord's improved algorithm and NAT traversal.Last, the P2P-SIP terminal will be designed and implemented, including node discovery, insert, find, stability, leaving, user registration and call setup with the example of SIP message. The performance of P2P-SIP will be analyzed through the compare and evaluation with traditional SIP terminal based on central server.