Web Proxy Caching Model Web Servers Aggregate Workload Proxy server We use prowgen to synthesize several wklds in which only one xtic under study is varied. The workload represents the aggregate wokld of the clients accessing the proxy. For each workld under study, we vary the repl. Policy at the proxy and the hit ratio and byte hit ratios were measured at different cache sizes during the simualtion. I will briefly show some of the results of the simulations. Web Clients

Factors and Levels Cache size Cache Replacement Policy Recency-based LRU Frequency-based LFU-Aging Size-based GD-Size Workload Characteristics One-timers, Zipf slope, tail index, correlation, temporal locality model

Performance Metrics Document Hit Ratio (DHR) Byte Hit Ratio (BHR) What percentage of the documents requested by the clients are satisfied directly by the proxy, without having to obtain from the Web server? Byte Hit Ratio (BHR) What percentage of the bytes requested by the clients are satisfied directly by the proxy, without having to obtain from the Web server?