Security and Trust Based Model for Peer To Peer System

Peer to peer is an advanced computer networking where all computers contribute to equivalent task for processing data. A Peer to peer network can be an ad hoc connection in which a pair of computers attached by means of a universal serial bus to transmit files. Security is not much effective in this type of systems it is because if the connections are not fixed to the computers appropriately then there will be difficulty in accessing certain files and the relationship is untrusted. Hence security in peer to peer systems is complex since disputes are created by lack of integrated authority. A new hybrid trust algorithm is used in this paper to facilitate a peer to reason about reliability of other peers based on earlier period interactions and recommendations. Both local trust value and global trust value is calculated while downloading from peer to peer system. Interactions and recommendations are assessed based on recentness, importance and peer satisfaction factors. Diffie–Hellman key exchange establishes a shared secret that can be used for secret communications while exchanging data over a public network. RSA algorithm (Rivest, Shamir, Adleman) based on Asymmetric key cryptography which ensures timely accessibility of reputation information to other peers along with security. The approach is to summarize the earlier period performance of the peer in its digital reputation and then predicting its deeds pertaining to future. The information shared among the peers is encrypted and decrypted using RSA Signatures. Thus malicious activities are prevented in peer’s reputation. The experiment is carried out using Java programming and the simulation results revealed that the RSA algorithm implemented using public key cryptography is protected and well-organized in a decentralized peer to peer network. Better peers were capable to figure confidence connections in their immediacy and detach malicious peers.