Coupling caching and forwarding: Benefits, analysis, and implementation
Résumé
A recent debate revolves around the usefulness of pervasive caching, i.e., adding caching capabilities to possibly every router of the future Internet. Recent research argues against it, on the ground that it provides only very limited gain with respect to the current CDN scenario, where caching only happens at the network edge.
In this paper, we instead show that advantages of ubiquitous caching appear only when meta-caching (i.e., whether or not cache the incoming object) and forwarding (i.e., where to direct requests in case of cache miss) decisions are tightly coupled. Summarizing our contributions, we (i) show that gains can be obtained provided that ideal Nearest Replica Routing (iNRR) forwarding and Leave a Copy Down (LCD) meta-caching are jointly in use, (ii) model the iNRR forwarding policy, (iii) provide two alternative implementations that arbitrarily closely approximate iNRR behavior, and (iv) promote cross-comparison by making our code available to the community.