Active Protocols for Agile Censor-Resistant Networks

Robert Ricci and Jay Lepreau

May 2001

Flux Research Group
School of Computing
University of Utah
50 S. Central Campus Drive Rm. 3190
Salt Lake City, Utah 84112-9205 USA


In this paper we argue that content distribution in the face of censorship is a compelling and feasible application of active networking. In the face of a determined and powerful adversary, every fixed protocol can become known and subsequently monitored, blocked, or its member nodes identified and attacked. Frequent and diverse protocol change is key to allowing information to continue to flow. Typically, decentralized and locally-customized protocol evolution is also an important aspect in providing censor-resistance.

A programmable overlay network can provide this type of manually-initiated protocol diversification. We have prototyped such an extension to Freenet, a peer-to-peer storage and retrieval system whose goals include censor resistance and anonymity for information publishers and consumers.

Full paper presented at and appears in Proceedings of the Eighth IEEE Workshop on Hot Topics in Operating Systems, May 2001:

The slides from the HotOS talk are available as: The thesis underlying this paper is also available (August 2001).