Perceptive Forwarding Strategy in Content-Centric Network

The Content-Centric Network (CCN), as a promising communication architecture for future networks, is still facing many challenges. In CCNs, it is difficult for the routing protocols, evolved from the proactive routing protocols in the current Internet, to discover temporary content replicas spread in router caches in time. This paper proposes a perceptive forwarding strategy (PFS) to perceive closer temporary content replicas to respond the users´ requests quickly. In our proposal, a new data structure, called a chunk map (CM), cooperating with an improved cache replacement policy is designed to indicate the availability (or unavailability) of the content replicas in a router cache. An additional Interest packet is conditionally forwarded to probe the cached replicas while a CM, piggybacked in a Data packet as a response, is distributed to the forwarding routers. Moreover, an improved cache replacement policy would cooperate with the CM to temporarily prevent replacing the content replicas indicated available by a CM in a router´s cache. The simulation result shows that our proposal has an outstanding performance in terms of the downloading delay and bandwidth consumption.