Data Size Aware Forwarding in Opportunistic Mobile Networks

With the proliferation of mobile devices, sending data by taking advantage of the opportunistic contact in an opportunistic mobile network (OMN) becomes a hot topic. Many previous data forwarding schemes assume that content can always be entirely transmitted over a single contact. However, with the increase of data sizes, such an assumption may no longer hold. In this paper, we propose a data size aware forwarding (DSAF) scheme for OMNs. Our method dynamically discovers the maximum transmission unit of an arbitrary path (PMTU) so that the source can adjust the amount of data to send in each transmission. Since the performance of DSAF is largely dependent on the latency to get the Message Too Big (MTB) feedback message, we first conduct theoretical analysis of the latencies for the receiver(s) to receive MTBs and then compare our theoretical results with the practical ones using a real trace. Simulation results show that our theoretical values closely match the practical ones and our DSAF scheme implemented by additive and multiplicative decrease flavors have low overhead compared with the benchmark algorithm where PMTU is pre-known.