Survey on the Present State of the Art of P2P Networks, Their Security Issues and Counter Measures
Peer to Peer (P2P) networks are quite different from traditional client server networks. In P2P systems, all nodes are equal or peers and they can either act as client or server. All the nodes have similar capabilities. These networks became ubiquitous for file sharing and performing operations in distributed fashion. P2P networks are overlays on top of Internet or wide area network. P2P networks such as Gnutella, Napster, BitTorrent, and Freenet are some of the existing applications that allow sharing resources and searching for resources. Direct exchange of resources is made possible with P2P networks provided there are certain mechanisms such as directory service, distributed hash table, and flooding to discover services. P2P networks have the potential to enhance the capabilities of networks with sharing of music, video, and other services. Nevertheless, the P2P networks throw security challenges as the nodes are vulnerable to various attacks. In this paper we review the P2P networks, their security issues and counter measures. The attacks include DoS, DDoS, Man in the Middle, Worm Propagation, Pollution Attack, Rational Attack, Sybil Attack and Index Poisoning Attack. This paper also provides counter measures of these attacks as available in the literature. The insights in this paper provide broad overview of P2P network issues and solutions.