Statistical Disclosure: Improved, Extended, and Resisted

TL;DR

This paper enhances a traffic analysis attack called 'statistical disclosure' and proposes a defense that significantly delays the attacker's ability to extract useful information from secure communications.

Contribution

It introduces an improved version of the statistical disclosure attack and a novel defense mechanism to mitigate its effectiveness.

Findings

The improved attack is more efficient and effective.

The proposed defense significantly delays attacker success.

The defense increases the amount of traffic observations needed for attack.

Abstract

Traffic analysis is a type of attack on secure communications systems, in which the adversary extracts useful patterns and information from the observed traffic. This paper improves and extends an efficient traffic analysis attack, called "statistical disclosure attack." Moreover, we propose a solution to defend against the improved (and, a fortiori, the original) statistical disclosure attack. Our solution delays the attacker considerably, meaning that he should gather significantly more observations to be able to deduce meaningful information from the traffic.