Efficient Unobservability against Strong Adversaries

We present Decentralized Unobservable Reporting Protocol (DURP), a low-latency, low-overhead, decentralized protocol for anonymous, unobservable communication to untrusted recipient. DURP ensures unobservability against global eavesdropper (and malicious participants), in contrast to known low-latency protocols such as Tor. DURP design is a modular combination of a simple queuing module, ensuring fixed rates for several events, together with an anonymization module, which can simply use existing anonymous protocols, specifically, either Onion-Routing (DURP) or Crowds (DURP). For length restrictions, we focus on network properties of DURP, e.g., latency. We found, using analysis backed by simulations, that DURP ensures reasonable latency and overhead. Our analysis allows configuring DURP for best trade-off of network properties.