Energy-Aware Social-Based Multicast in Delay-Tolerant Networks

In Delay-Tolerant Networks (DTNs), nodes forward data opportunistically upon contact because of irregular connectivity and low network-denseness. In this type of networks, energy plays an important role in successful data delivery and enhancement of network lifetime. To address the problem of selecting appropriate relay nodes for data forwarding, recently researchers are using concepts of social networks in the design of DTN routing schemes. This is because of its ability to make forwarding decisions based on the knowledge of long-term and more stable social characteristics of the nodes. In this paper, we propose an energy-aware relay selection scheme to support multiple multicast sessions based on an existing social-based single-data multicast scheme. The proposed scheme selects relays for delivering data to the destinations based on the centrality, one of the important social network characteristics, as well as on the residual energy of the DTN nodes. Our proposed scheme is shown to have polynomial-time complexity. We claim that our scheme supports higher number of multicast sessions thereby maintaining longer lifetime of the network while achieving required data delivery ratio compared to a prominent single-data multicast scheme. Our claim is validated through quantitative performance analysis.