It is no secret that the Internet world has now evolved rapidly. Different types of texts and multimedia have congested our network traffic. This situation causes much lagging in the current workplace or geographic area. One of the infrastructures that support and convey data is a proxy server. Proxy server needs efficiently to use historical data to give users best links and also to reduce the traffic congestions. Furthermore, historical data are stored in a data warehouse for further processing. From the data warehouse, the best hit ratio can be obtained and, which increases the probability to keep the cache object for proxy server to serve the client faster. In order to get the hit ratio, rough set algorithms are applied to mark the lower and upper approximation and to get the best results.