University of Illinois at Urbana Champaign
Distributed Hash Table (DHT) lookup is a core technique in structured Peer-to-Peer (P2P) networks. Its decentralized nature introduces security and privacy vulnerabilities for applications built on top of them; thus set out to design a lookup mechanism achieving both security and anonymity, heretofore an open problem. The authors present Octopus, a novel DHT lookup which provides strong guarantees for both security and anonymity. Octopus uses attacker identification mechanisms to discover and remove malicious nodes, severely limiting an adversary's ability to carry out active attacks, and splits lookup queries over separate anonymous paths and introduces dummy queries to achieve high levels of anonymity.