Resilient P2P anonymous routing by using redundancy

One hurdle to using peer-to-peer networks as anonymizing networks is churn. Node churn makes anonymous paths fragile and short-lived: failures of a relay node disrupt the path, resulting in message loss and communication failures. To make anonymous routing resilient to node failures, we use a simple yet powerful idea based on message redundancy by erasure coding and path redundancy to mask node failures. We present an allocation of erasure-coded message segments among multiple paths that provides a guideline on how to maximize routing resilience upon different node availabilities in real-world systems. Our approach allows a tradeoff between routing resilience and bandwidth usage. We show that our approach greatly improves routing resilience while only incurring a moderate bandwidth overhead.