Intra-AS cooperative caching for content-centric networks

Abstract

The default caching scheme in CCN results in a high redundancy along the symmetric request-response path, and makes the caching system inefficient. Since it was first proposed, much work has been done to improve the general caching performance of CCN. Most new caching schemes attempt to reduce the on-path redundancy by passing information on content redundancy and popularity between nodes. In this paper, we tackle the problem from a different perspective. Instead of curbing the redundancy through special caching decisions in the beginning, we take an orthogonal approach by pro-actively eliminating redundancy via an independent intra-AS procedure. We propose an \textit{intra-AS cache cooperation} scheme, to effectively control the redundancy level within the AS and allow neighbour nodes in an AS to collaborate in serving each other's requests. We show via trace-driven simulation, that intra-AS cache cooperation improves the system caching performance and reduces considerably the traffic load on the AS gateway links, which is very appealing from an ISP's perspective.