Analysis of Speculative Prefetching

Abstract

Prefetching is a potential method to reduce waiting time for retrieving data over wireless network connections that commonly occur in mobile scenarios. These connections typically exhibit low bandwidth as well as high latency. This article analyzes fundamental principles in speculative prefetching. Based on a simplified system model, the influence of parameters and strategies on prefetching performance is investigated, both analytically and in simulation. The reduction of the mean waiting time is used as performance metric. An example is given that makes use of the Zipf distribution to demonstrate the influence of the documents' probability distribution and its parameters. A low-complexity algorithm that performs optimally under the given assumptions is presented.