CORD: Content oriented routing with directories

Recent proposals for content routing in information-centric networks (ICN) require the use of content-based routing tables listing routes to name prefixes or individual named data objects (NDO), and a single naming space for NDOs. We present CORD (Content Oriented Routing with Directories) as an alternative to content routing in ICNs. CORD eliminates the need for large content-based routing tables by establishing routes to directories using distance-vector signaling and by mapping name prefixes or names of NDOs to directories using publish-subscribe mechanisms. Simulation experiments using the topology of a real ISP network are used to compare CORD with name-based content routing approaches based on link-state and distance information. The results show that CORD attains comparable data delivery and end-to-end delays, but incurs orders of magnitude less control overhead. In addition, CORD supports multipath forwarding of content requests and content.