Optimization On P2P Of Audio And Video Using SIP And ICE

In recent years, with the rapid development of Internet technology, users areincreasingly focused on the real-time and authentic interaction in the way of socialnetworking. The network technology of real-time audio and video communications whatsocial networking needs is booming, therefore it brings increasing concern. Currently, thenetwork audio and video communications are not widely used, not only because of the poorexperience caused by network bandwidth, but also because of the transmission of audio andvideo streams without high efficiency and good applicability. So how to make real-time audioand video communications transmit data streams by means of P2 P in a variety of networktopology is crucial.When studying the theory knowledge of P2 P and NAT and learning the technology usedby the audio and video communication, on the basis of SIP which is used as a control signaland ICE which is used by NAT accrossing, an optimized scheme is put forword in the thesiswith innovation. The scheme aims at improving the efficiency of P2 P in audio and videocommunications, not only an improved port prediction model is implemented, but also theprocess of ICE is optimized. In the port prediction model, a specialized server used to allocateports is designed for distributing port resourses under different NATs. After NAT mapping, thenetwork outside ports can be obtained. Analyzing the obtained ports and guessing the nextport which will be distributed for the new session in the NAT. Then using the guess port forICE, realizing P2 P with symmetrical NAT, which is a key problem that ICE can not realizebefore. The port prediction model can improve the applicability and the success rate of P2 P.Additionally, there are two steps in the optimization for the process of ICE to reducing thenegotiations time. One is intelligently forming the inspection list, and the other is simplifyingthe connecting process in ICE.With applying the improved solution to the actual system, a large number of tests anddata collections are performed under the IP public network environment for the test system.Each functional module of the optimization solution is tested and verified. At last, comparingand analysising the data. The analysis results successfully validate that the optimized schemeimplements the audio and video stream transmitting directly through P2 P under symmetricNAT, instead of relaying by server. The result also shows that the optimized scheme simplifiesthe process of ICE.