Tor: The Second-Generation Onion Router

We present Tor, a circuit-based low-latency anonymous communication service. This second-generation Onion Routing system addresses limitations in the original design by adding perfect forward secrecy, congestion control, directory servers, integrity checking, configurable exit policies, and a practical design for location-hidden services via rendezvous points. Tor works on the real-world Internet, requires no special privileges or kernel modifications, requires little synchronization or coordination between nodes, and provides a reasonable tradeoff between anonymity, usability, and efficiency. We briefly describe our experiences with an international network of more than 30 nodes. We close with a list of open problems in anonymous communication. 1 Overview Onion Routing is a distributed overlay network designed to anonymize TCP-based applications like web browsing, secure shell, and instant messaging. Clients choose a path through the network and build a circuit, in which each node (o...

• Type: Conference
• Year: 2004
• Where: USS
• Authors: Roger Dingledine, Nick Mathewson, Paul F. Syverson
• Keywords: Onion Routers, Onion Routing, Operating System, Perfect Forward Secrecy, USS 2004