Congestion- and selfishness-aware social routing in delay tolerant networks

Delay Tolerant Network (DTN) is a type of network that permanent connections between nodes are not always available. Routing in DTN uses store-carry-and-forward scheme, where nodes store and carry data until a suitable message carrier appears. Positive social characteristics such as centrality and friendship can be used to make a better routing decision in DTN. However, negative social characteristics such as selfishness may decrease the network performance. Selfish nodes for their individual or social benefits, do not contribute in message relaying when the device resources like battery level are low. Moreover, to achieve a better network performance we need to consider buffer congestion at the rely node. In this paper, we propose Congestion Aware and Selfishness Aware Social Routing protocol (CASASR) which by using social characteristics and awareness of buffer congestion and selfish behavior in the network selects a better relay. Using Poisson process, we find a utility value to select a relay node with a higher chance to deliver the message to the destination in the remained message TTL. In addition, we take into account the social and individual selfish behavior of nodes to adjust energy level available for message relaying. Comparison of our algorithm against several well-known algorithm shows that CASASR performs better in terms of delivery ratio and delivery overhead.