Research On Proxy Cache In A Cluster-Based Web Caching System

With the rapid expansion of Internet, it has come forth that the delay ofaccess, the heavy loads of web servers and so on. Web proxy caching techniqueprovides a solution to the above problems. It is now widely applied on Internet.However, with the rapid increase in clients and web flux, the performance ofsingle cache can hardly satisfy this situation. Therefore, it has great actualsignificance to research on proxy cache in a cluster-based web caching systemin the article. Several aspects are probed into as follows:Firstly, in the store of cached objects, aiming at not paying attention to therelationship of information, the site-oriented cache structure is used to supportintelligent process better.Secondly, in the management of cached objects, aiming at not combinedreplacement policy with consistency policy, a new algorithm called RCA(Replacement Consistent Arithmetic) is proposed and designed. It can reflectweb access characteristics better and calculate easily. It shows the superiorityof combining cache replacement policy with consistency policy.Thirdly, in the communication among cache proxies, NCPCP(NewCooperative Proxy Cache Protocol) is proposed. By using redirection, thecommunication in the system will be greatly reduced;using access registerform, the load on the manager will also be reduced. Only the request will besent to the peer proxy, so the redundant duplicates among proxies are greatlyreduced. The whole hit-rate is increase correspondingly.Finally, after analyzed in theory, it is proved that the performance ofNCPCP is better than CRISP(Caching and Replication for Internet ServicePerformance) and ICP(Internet Cache Protocol). It is also proved that the wholehit-rate of NCPCP is higher than that of CRISP and ICP in our experiment.Some precious experience is provided for the future research.