The Research Of The File Authenticiation Protocol

With the development of peer-to-peer (P2P) technology, it is becoming more and more important and has applications in more and more new fields. Security in P2P systems has become a challenging problem due to the autonomy and Ad-hoc connectivity. In the data sharing based P2P systems, one of such issues is how a user can anonymously determine whether the file he/she downloaded is an authentic copy. Currently, many research groups established by big companies and famous universities devote on security issues in decentralized P2P systems.First this paper introduces the background and significance of Peer-to-Peer, illuminates its advantages and applications compared to Client/Server model and pointes out their security issues. Then some File Authenticity Protocols are described and appraised for their merits and disadvantages. We also classify anonymities and explain anonymity degree of some protocols. We introduce the Pseudo Random Trust which combines authority and anonymity, and improve its resistance of man-in-the-middle attack, By using the negotiated of key to encrypt data between the initiator and receiver.A File authentication protocol based on electronic voting (FAP-EV) is presented. The initiator asks a number of proxies to flood an electronic voting and return their collected tickets. The initiator audits returned tickets and determines which file is the authentic copy of the documents. The protocol archives initiator anonymity, voter anonymity and provider anonymity by the help of onion routing and switching route table. Theoretical analysis and experiential simulation show that the protocol can successfully authenticate the authenticity of the searched file with a probability more than 95%. Compared with existing file authentication protocols, it reduces communications and provides anonymity of participants.