ABSTRACT
This chapter discusses routing in Delay- and Disruption-Tolerant Networking (DTN) and its challenges. Since DTN scenarios and applications can vary widely in terms of their characteristics and requirements, no single solution that fits all DTN scenarios has yet been identified. The chapter also reviews existing DTN routing approaches and protocols. It starts with an overview of routing in the Internet. In the Transmission Control Protocol/ Internet Protocol Internet, routers participating in the routing process build routing tables which, for a given destination address, determine the router's outgoing interface. Existing DTN routing approaches focus on trying to maximize end-to-end data delivery under episodic end-to-end connectivity. As such, DTN routing can be classified in two major categories, namely: Replication-Based Routing and Forwarding-Based Routing. The main focus of Contact Graph Routing extension block is "source path routing", i.e., annotating the bundle with the best computed route as determined at the source node. DTN routing follows the store-carry-and-forward paradigm, an extension of traditional store-and-forward.
