Mixmaster Vs Reliable: a Comparison of Two Anonymous Remailers

Architecture and Background

Len Sassaman,Mixmaster vs. Reliable: A Comparison of Two Anonymous Remailer Applications The "Type II" remailer network has been operating since 1995, providing strong anonymity email services to the public.

Vulnerability Analysis

We recently performed an analysis of the anonymity provided by the two independent implementations of the Type II protocol. This is joint work with Claudia Diaz and Evelyne Dewitte, to be presented at the ESORICS conference in September.

Exploitation and Demonstrations

This talk will discuss the methods used to evaluate the anonymity provided by Mixmaster 3.0 and Reliable 1.0.5. It will explain the threat models considered for email anonymity and known attacks agaist them, highlight the differences in the mixing algorithms used, identify potential areas of weakness in the applications, and explain the reasoning behind the different design decisions in the two applications.

Remediation and Defensive Strategies

Len Sassaman is a communication security consultant specializing in Internet privacy and anonymity technologies. Formerly the security architect for Anonymizer and a software engineer for PGP Security, Len is now focusing on research in the area of practical attack-resistant anonymity systems which can be widely deployed and used by large groups. Additionally, Len is an anonymous remailer operator, and maintainer of the oldest actively-used anonymity software, Mixmaster.