SimRouter: Message routing based on Similarity and Relative Probable Positions of nodes in DTNs

Delay tolerant networks (DTNs) have the major challenge of unpredictable topology due to nodes’ mobility and intermittent connections between nodes. Researchers have proposed various routing schemes to route packets effectively and efficiently within the given constraints, but we are still far from a perfect protocol. We propose a novel multi-copy protocol SimRouter for such networks, leveraging the additional information about the network, to make the routing decisions. SimRouter uses relative probable positions of the nodes and their similarity to route messages effectively with low overhead. Each node estimates and stores the relative probable positions of other nodes and a vector containing the number of times other nodes came in contact with it. The decision whether to replicate a message to another node or not is taken considering the two factors. Firstly, how similar the two nodes are in terms of their contact history and secondly, the relative positions of the nodes with respect to the destination node. The proposed protocol outperforms the current state of art multi-copy protocols specifically for high traffic loads.