Social-aware hierarchical multicast in Mobile Delay Tolerant Network

With the popularization of portable devices equipped with wireless communication capability, Mobile Delay Tolerant Network (MDTN) gets extensive attention of scholars. Infrastructureless networking with portable devices has become a typical scenario in MDTN. With regard to the infrastructureless MDTN scenario composed by portable devices, we propose a social-aware hierarchical multicast distribution algorithm (SAHM) which is suitable for this scenario. SAHM algorithm regards community detection, centrality computation and the prediction of contact rate. The community structure in the network is identified by K-Clique algorithm. On the basis of communities, we determine whether the meeting node can act as a relay node based on the C-Window centrality and the contact predictability. Intercommunity SAHM selects relays among those nodes whose contact rate is higher and higher than Pthresh. Intracommunity SAHM selects relays among those nodes whose C-Window centrality is high. In order to verify the performance of SAHM algorithm, we implement SAHM algorithm on the ONE simulation platform and compare whose performance with the existing classical algorithms on two real data sets (Infocom06 and Cambridge). Simulation results show that our proposed algorithm has similar data delivery ratio with the existing algorithms or higher than them, but significantly reduces data forwarding cost, making data more quickly and efficiently forward to the nodes which need data.