There Peer-to-peer(P2P) networks is that they are continually subject to Sybil attacks malicious nods can compromise the network by creating and directing large numbers of fictitious identities. In this paper, Sybil attacks may underscore the successfully of such schemes as malicious peers may use fake identities to synthetically manipulate the reputation. The levels of trust of several authentic and honest peers. Inthis mostly trusted certification, Reversing testing, Random key redistribution, Location/position verification and Reputation mechanisms methodology use. We analysis of the Sybil attack with respect to the resource chuck to operate Sybilnodes and we consider the calculableeffect of Sybil nodeson the total system. Reputation systems analyze reputation keep count according to its history of logs file.

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P2p Sybil Attack Sybil Resilient Trusted Management Free Riding Reputation Mechanism.