An analysis of World-Wide Web Proxy Cache performance and its application to the modelling and simulation of network traffic.

Previous studies of World-Wide Web traffic patterns have, quite necessarily, been limited in their scope. Without exception they have had to choose to represent either a client's [1] or a server's [2,3] point of view, or solicit user responses in interactive surveys [4,5]. In all of these cases the methodology is able to provide neither a complete nor an impartial picture of the activities being carried out on the Web. The unique position of the HENSA Unix proxy cache, sitting between large numbers of clients and servers, means that over the past two years we have been able to monitor and analyse several hundreds of millions of transactions on the World-Wide Web. In this paper we present our findings as far as traffic trends are concerned. These trends show both the growth of the Web and typical characteristics of a large volume of Web traffic. The configuration of the HENSA cache has changed significantly over the two years of its existence, and one of the purposes of this study is to better understand the demands placed upon large proxy caches, in an effort to simulate and model more effective cache configurations.