Abstract
In this paper we present TAP, a novel Tunneling approach for Anonymity in structured P2P systems. An important feature of TAP is that anonymous tunnels are fault-tolerant to node failures. Relying on P2P routing infrastructure and replication mechanism, the basic idea behind TAP is to decouple anonymous tunnels from "fixed" P2P nodes and form anonymous tunnels from dynamic tunnel hop nodes. The primary motivation of TAP is to strike a balance between functionality and anonymity in dynamic P2P networks. We have implemented the tunneling mechanism in Java on FreePastry 1.3. An analysis of its anonymity and performance was evaluated via detailed simulations.