Abstract
Sybil attack is considered one of the most damaged attack that menace structured p2p overlay networks. It's the most sophisticated node active, used for a variety of illicit activities. A key requirement for these activities is the ability of such malicious user to generate a huge number of node identifiers and possibly choose some of them in order to disrupt availability and integrity in such systems. This paper highlights the problem of Sybil attack and presents a Sybil tracking process to deal with such problem. (C) 2014 Published by Elsevier B.V.