Based On A Hybrid P2p Network Model Of Ip Phone Technology

With the rapid development of the communication and computer technology, the technology of voice over internet protocol has been applied extensively. Now the mostly of VoIP are base on client/server mode, it is the concentricity network, so it faces many problems. The P2P overlay systems can make the full use of the resource and capability of every node in the network, it inherently has high scalability, robustness and fault tolerance because there is no centralized server and the network self-organizes itself. And the same time, the SIP protocol has many advantages as simple, easy to extend, convenient for realization, so it choosed as the kernel control protocol of NGN/IMS and 3GPP.This paper aim to the shortages of the traditional VoIP system, bring forward the VoIP solution which base on the P2P overlay systems, and construct the network Architecture which combines the concentration and distribution. And the paper compares the advantage and disadvantage of the two main VoIP protocols: H.323 and SIP, then choose the SIP protocol as the login, router update and call control protocol. On the other hand, the paper designed the two main equipments of design server and node, and bring forward the realize method base on the analyze of technology such as signal protocol, voice codec, network address translator (NAT)/firewall traversal.The P2P protocol Chord is a scalable protocol for lookup in a dynamic peer-to-peer system with frequent node arrivals and departures. The consistent hash function assigns each node and key an m-bit identifier using a base hash function such as SHA-1.And last, within the practicing, the author choose the open-source projects as the develop environment, which include oSIP,OPAL,Chord, etc. And realized the development the system software.From the result of simulation, it is proved that the DHT router algorithm has excellent stability, it shown that even massive failures have little impact on robustness. The realization of this system establish the foundation for the research of the P2P communication technology...