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Detecting and isolating pollution attacks in peer-to-peer VoD systems

In recent years the demand for video streaming services has escalated resulting in high bandwidth costs of the service providers. To address this challenge a number of recent research efforts have focused on offloading media servers using P2P architectures, however they all fall under the assumption that the participating peers are in general cooperative. Ignoring security issues can significantly deteriorate the system's efficiency especially in real P2P systems where it is highly probable that at least one peer will have malicious behavior. The malicious peer can perform an attack to the system by polluting the video blocks that are exchanged, thus deteriorating the QoS. In this paper, we present a distributed P2P VoD system that is capable of identifying and isolating a malicious peer causing pollution. Its components that manage the overlay and the data scheduling are tested under diverse simulations that show promising results.