OS-multicast: On-demand Situation-aware Multicasting in Disruption Tolerant Networks

Disruption tolerant networks (DTNs) are emerging solutions to networks that experience frequent network partitions and large end-to-end delays. In this paper, we study how to provide high-performance multicasting service in DTNs. We develop a multicasting mechanism based on on-demand path discovery and overall situation awareness of link availability (OS-multicast) to address the challenges of opportunistic link connectivities in DTNs. Simulation results show that OS-multicast can achieve a better message delivery ratio than existing approaches, e.g. DTBR (a dynamic tree-based routing), with similar delay performance. OS-multicast also achieves better efficiency performance when the probability of link unavailability is high and the duration of link downtime is large