Research And Application Of QoS Mechanism In CSCD System Based On P2P Model

Along with Internet and network technology developing rapidly,a new working method---CSCW has appeared.At the same time,Computer Supported Cooperative Design(CSCD for short),one of main applications of CSCW,gets more and more attention.P2P technology also can be called point-to-point technology.In P2P model each node has the same role: it can get service from other nodes and can supply service to other nodes synchronously.Because P2P model has the characteristic---all nodes are the same and can fulfill tasks cooperatively,the P2P model becomes a natural choose for the CSCD system.In the CSCD system based on P2P model,which type of data can be transmitted between users is not only text,but mostly is real-time stream such as video or audio;Each user in the same cooperative group may has different environment.All these problems such as the above mentioned,make the best-effort transmission service, the only service type which current network has, can not satisfy the actual applications'needs. Some QoS(quality of service) mechanism should be added into current transmission system in order to satisfy different users'needs.The thesis firstly introduces P2P network and CSCW system ,analyzing their QoS needs.Secondly the thesis describes the mainly QoS models—IntServ and DiffServ,giving their principles and differences.After that,the thesis mainly researches the QoS mechanism in the Linux System,specially the traffic control technology(TC for short).In according to the related theory researches and analysises,the thesis puts forwards the overall project of implementing QoS prototype system based on the the CSCD system using P2P model,then giving an detailed sub-system design. At last, the paper discusses the conclusion and future works.