File Sharing System Based On CL-PKC In P2P Networks

With the rapid development of the instant message software,file sharing system, streaming media players,office coordination system and so on,P2P technology has already had a profound impact on the internet.However,its own characteristics of decentralization,autonomy,dynamicity and isomerism made it to face many security problems which have greatly impeded the development of the P2P networks.Because of the complicated certificates management in the traditional Public Key Infrastructure(PKI) and the inherent key escrow problem brought by Identity-based Cryptosystems(ID-PKC),the problem of security in P2P networks can not be soluted very well.In this issue we made a deep research of the relevant technologies of P2P networks,and brought the bidirectional authentication protocol based on certificateless into P2P networks.This research provides a positive exploration to solve the security problems in P2P networks.In this issue we make a systematical research of the authentication based on CL-PKC in P2P networks,and propose a kind of bidirectional authenticated protocol based on the CL-PKC according to the characteristics of P2P networks.Then we build a file sharing system in P2P networks,and implemented the authenticated mechanisms based on the CL-PKC.The specific tasks consist of the following:1,We researched the secure signatures and authentication technology,and on the basis of respective analysis of the advantages and disadvantages of the PKI,ID-PKC and CL-PKC,we propose one kind of bidirectional authenticated protocols based on CL-PKC for P2P networks.2,We detailedly analysed working principles and coding of the P2P classical software BitTorrent,and the protocol of the JXTA development platform,then designed and realized a P2P file sharing system based on the JXTA platform in the Java development environment,which provides a practice platform to solve the security problems in P2P networks.3,We build a KGC server,then applied the bidirectional authentication protocol based on CL-PKC in the file sharing system.In this system we complete the peers' identity authentication,and realized the certificateless authentication mechanisms in P2P networks;we used the digital signature and Hash technology to implement the content authentication of the files in the system,which ensures the reliability and integrity of the transmitted data.This task provided not only an exploration to solve the P2P networks security problems,but also some valuable experience for solving the security problems of the other networks.