With　the　development　of　computer　technology　and　communication　technology,　network　communication　has　brought　great　convenience　to　people.　It　has　gradually　become　an　indispensable　part　of　people＇s　daily　life　and　work.　The　Internet　is　the　largest　computer　network,　and　the　rapid　development　of　the　Internet　benefits　from　the　emergence　of　client　/　server　(Client/Server,　C/S)　network　patterns.　Client　/　server　mode　is　the　basic　mode　of　traditional　network,　and　also　the　most　traditional　and　mature　centralized　mode　of　work　in　Internet.　Many　Internet　application　protocols　(such　as　HTTP,　FTP,　SMTP,　etc.)　have　adopted　this　mode.　As　the　implementation　of　distributed　computing　technology　is　one　of　the　forms　of　network　P2P　(Peer-to-Peer　Network),　because　there　is　no　centralized　control,　can　avoid　the　server　bottleneck　problem　of　C/S　network　mode,　and　can　meet　the　needs　of　users　between　the　direct　exchange　of　information,　to　achieve　a　free　Internet　environment.