NeTS: Small: Collaborative Research: ReDS: Reputation for Directory Services in P2P Systems

Indiana University, Bloomington IN

Investigators

Abstract

Peer-to-peer (P2P) systems are gaining popularity and importance for applications ranging from communications to content delivery over the Internet. Since such systems are inherently formed by a large collection of untrusted peers, their security and reliability can be adversely impacted by malicious peers in the system. In particular, P2P systems must provide a reliable decentralized directory service for locating peers with the desired content and services. If malicious peers are able to subvert directory lookups, the integrity of the system is greatly compromised. This project advances the state of the art in P2P security and reliability by applying reputation information at the directory level for improved success of subsequent lookups. The new systems will use information from successful and failed lookups, as well as the structure of the peer-to-peer system, to derive reputation information for various peers and estimate the locations of malicious nodes in the system. The project will also include an investigation into mechanisms to limit Sybil attacks, in which attackers attempt to overwhelm the system with malicious peers. The mechanisms will combine the use of social network links and the structure of the P2P system to create a robust identifier space for nodes, thus constraining how many Sybils can be introduced into the system. Through a combination of such techniques, the project will make P2P systems more trustworthy and reliable, directly impacting the millions of users who already make use of such systems today.