SnLocate: A Location-Based Routing Protocol for Delay-Tolerant Networks

Delay-Tolerant Networks (DTNs) are networks where there are no permanent end-to-end connections, that is, they have a variable topology, with frequent partitions in the connections. Given the dynamic characteristics of these networks, routing protocols can take advantage of dynamic information, such as the node’s location, to route messages. Geolocation-based routing protocols choose the node that moves closer to the location of the message destination as the message carrier. However, such protocols suffer from obsolete location information due to node mobility and network partitions. In this chapter and conversely to the state-of-the-art, an epidemic-based decentralized localization system (i.e., DTN-Locate) and a hybrid location-based routing (i.e., SnLocate) are proposed. The former is used for disseminating node’s localization information meanwhile the latter to create and route multiple copies of a message, using geographic mechanisms to disseminate them. Besides, a novel distributed contention mechanism is also proposed. The performance evaluation shows that the SnLocate protocol has a higher delivery rate and lower latency than other geographic and non-geographic routing protocols considered.