Design and Implementation of Simulator of Web Object Access Characteristics

Web object caching is one of the most prevalent approaches for improving Web performance. Caching can be applied at several locations: at the client, at the proxy server, at the server. Research shows that the hit ratio of web caching can reach 30% - 50%. The most important problem in the application of web caching is how to manage web cache efficiently. Studying the web access characteristics is the foundation for managing web cache efficiently. Web LOG generation simulator plays an important role in studying web caching system. So far there are two approaches for synthesizing web access workloads: the trace- based approach and the mathematical analytical approach. The trace- based approach uses a history trace to generate a new workload. The mathematical analytical approach creates mathematical models to generate workloads. After analysing the web object access characteristics, this paper uses mathematical analytical approach to design and implement a web LOG simulator: WEBSIM, in which the web object popularity distribution, web object size distribution and web temporal locality are simulated. WEBSIM not only can synthesize web object access workload, but also has higher flexibility, and provides base for further web caching and prefetching study.