Workload Period

Characterizing World Wide Web proxy traac helps identify parameters that aaect caching, capacity planning and simulation studies. In this paper we identify invariants that hold across a collection of ten traces representing traac seen by caching-proxy servers. The traces were collected from governmental, industry, university, high school, and an online service provider environment, with request rates that range from a few accesses to millions of accesses per hour. We also show that the examined traac is self-similar. We explore sources of Web self-similarity and we conclude that a strong source is the periodicity in the users behavior. The tests revealed that their is a strong connection between access rate from hour to hour. We also report the hit rate and weighted hit rate obtained by running a trace driven simulation on the workloads to simulate a proxy with innnite cache. similarly, accesses to unique servers and URLs are a small portion of the total. By considering these characteristics of traac we can improve the utility of caching for WWW clients.