Research Of The Key Technology Of P2P-Based Live Media Streaming System

Along with the development of the network technology, the network multimedia service finds the extensive application. As a new network technology, P2P changes the traditional transmission mode, which has a core server. Each peer on the P2P system is not only a consumer, but also a provider. If we divide media stream into small segments and transmit them on P2P system, each peer on the P2P system can be the provider of each segment so that the server bottleneck of current existing systems is fundamentally overcomed. Therefore, more and more scholars begin to study the P2P-based live media streaming system.This thesis introduces a P2P-based live media streaming system structure, and investigates two key techniques including NAT traversal and application multicast layer tree.The top structure is the foundation of the P2P-based live media streaming system structure. This thesis discusses and improves the application multicast layer tree model by means of the establishment plan based on the application lever multicast tree of single tree structure to build a multicast tree which takes low delay and low connection pressure in order to realize multicast on application layer according to adjacent principle of network address. This plan implements dynamic equilibrium control of network better, and raises the efficiency of the medium stream data transmission.The equipments of NAT may cause the fail of direct connection in P2P. In order to improve the reliability of NAT traversal, this thesis researches into the TCP NAT traversal model, and statements a plan of TCP penetrates NAT from the viewpoint of the engineering application, which reduces the dependence of the server and be more safely and efficiencilly when connecting. It improves the reliability of NAT traversal, on the premise that broadcast quality is guaranted.