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Review and analysis of web prefetching

Web caching is widely used to cache resources that have already been used and reuse them in near future. Prefetching, in comparison, is a technique to cache resources that have never been used. The core of prefetching is prediction - predicting which resources might be used in the the near future. Prefetching is a technology that has been actively studied in the recent years. Most of the modern browsers have built-in mechanisms for prefetching. Some modern websites also add prefetching support to enhance performance. Although prefetch can reduce user-perceived latency, it may increase bandwidth requirements, cause security issues, and trigger unexpected actions. This paper reviews prefetching features of some of the most popular modern web browsers and websites and discusses the problems that prefetching could cause.