Credit-based Cooperation Enforcement Scheme in Delay Tolerant Network

Abstract

Delay tolerant network(DTN) is a network which provide a promising solution to support various applications in the regions where connectivity of end-to-end network is not available. In Delay tolerant networks(DTNs) , the intermediate nodes which are on a communication path between source and destination are expected to store, carry and then forward the bundles which also called in-transit messages in opportunistic way. This is called opportunistic data forwarding. Such kind of forwarding method depend on the assumption that each node in the network is ready to forward bundles for other nodes in the network. This assumption can be violated. Because there may be some selfish or malicious nodes, which may not forward bundles for others and work as bundle relays. Selfish nodes may do this because they do not want to waste their resources to relay bundles of others. To give solution to this problem , we propose credit-based cooperation enforcement scheme. This scheme stimulate selfish nodes to take part in forwarding process. In this scheme some incentives are given in favor of message forwarding by selfish nodes. In this scheme, credits are given to each selfish node lies on forwarding path if bundle is successfully delivered to final destination. In this way, we can achieve better network performance by stimulating selfish nodes to take part in forwarding process.