Transparent en-route cache location for regular networks

Caching improves network and system performance for WWW browsing. The way caches are currently deployed requires clients or caches to be aware of the location of nearby caches. This creates management and connguration problems, which may also lead to performance bottlenecks. In contrast, Transparent en-route caches (TERC) are devices that are placed at appropriate locations within the network and work obliviously. A TERC snaps web requests and web data. If the requested item exists in the TERC's memory, the data is sent to the requester, otherwise the request is transparently forwarded up the routing path. In this work, we study the important problem of where to place network caches, and in particular, TERCs. This problem is intractable for general networks, and thus we concentrate on regular topologies namely lines and rings. We give both a general dynamic programming algorithm, and closed formulas for some special cases. Our results demonstrate both the signiicant saving achieved by using TERCs, and the importance of placing the caches in the optimal locations.