An improved MaxProp based on neighborhood contact history for Delay Tolerant Networks

Delay Tolerant Networks (DTNs) are intermittently connected mobile networks, in which a fully connected path from source to destination does not exist. Therefore in these networks, message delivery relies on opportunistic routing where nodes use store-carry-and-forward paradigm to route the messages. However, effective forwarding based on a limited knowledge of contact behavior of nodes is challenging. In some routing algorithms, (such as Prophet [1], MaxProp [2]) the messages are forwarded to nodes which has higher chance to meet the destination. The MaxProp was designed for vehicle based DTN. It has some drawbacks. For instance, during normalization step of updating delivery probability, it drastically decrements the delivery probability for the nodes corresponding to older encounters. On the other hand, it increments one node's delivery probability, corresponding to the latest encounter to a great extent. This procedure of updating delivery probability can suffer from non-optimal routing decisions. In this paper we propose a new technique for updating delivery likelihood based on neighborhood contact history. For the simulation, we have used Opportunistic Network Environment (ONE) Simulator. The simulation shows that our proposed technique performs much better than original MaxProp.