Design of a cache management scheme for gateways on the vehicular telematics network

Abstract

This paper proposes and measures the performance of a cache management scheme for vehicular telematics network so as to provide an advanced route recommendation service, concentrating on gateways which relay information between a specific server and vehicles. As an enhanced version of pure FAR (Furthest Away Replacement), the proposed scheme 1) replaces Euclidean distance by network distance in estimating the distance to a data item, 2) binds each cache item to a link in the target road network, 3) introduces a directional weight to consider the directional tendency of current traffic flow, and finally 4) schedules the cache requests according to their angular locations to efficiently deal with the multiple pending requests. Simulation results, conducted using the real-life trajectory data obtained from a tracking system currently in operation, show that the proposed scheme can improve the cache hit ratio by up to 9.2 %, compared with FAR as well as that the proposed angle-based scheduling scheme can further improve the cache hit ratio by up to 2.3 %. © 2009 Springer Berlin Heidelberg.