The Medusa Proxy

Introduction:

The Medusa proxy is a non-caching forwarding proxy. It was designed to explore user-perceived Web performance. It is typically configured as a personal proxy for the Web browser and executes alongside the browser on the same machine. Medusa has a number of features, including:

The Medusa proxy can install filters to transform HTTP requests.
As it receives requests, the Medusa proxy can record them in a trace for subsequent replay in non-interactive experiments.
Different download optimizations can be toggled in the Medusa proxy during object requests, such as the use of parallel and persistent connections.

Additional Studies:

A short follow-up study to the Whole Page Performance study was done. We found that using parallel connections improves whole page performance by the most substantial amount. This led to the question of just how many parallel connections were being used by browsers to download pages.

Parallel Connections Under Two Browsers. We examined the number of parallel connections used by two different browsers (IE 6.0.26 and Netscape 4.79) for several different web pages (chosen for persistent connection support). We looked at both how many parallel connections are opened in general and how many are opened to the same server.

Papers:

The Medusa Proxy: A Tool for Exploring User-Perceived Web Performance. Mimika Koletsou and Geoff Voelker. In Proceedings of the 6th annual Web Caching Workshop. June 2001.
Whole Page Performance. Leeann Bent and Geoff Voelker. In Proceedings if the 7th International Web Content Caching and Distribution Workshop. August 2002. A more complete and corrected version of this paper can be found here.

Talks:

Whole Page Performance. Leeann Bent. Given at The 7th International Web Content Caching and Distribution Workshop. August 2002.

Downloads:

Download the Medusa Proxy here.

For additional info, contact: bent@cs.ucsd.edu.