A Broadcast Method Based on Estimation and Preservation of Stable Links in Delay Tolerant Networks

Delay tolerant networks (DTNs) are a class of networks that experiences frequent and long-duration partitions. In this paper, we propose a broadcast method that can achieve high message delivery ratio and low latency considering upper limit of links and latency of link establishments caused by implementations. In our proposal, nodes reduce the number of times of link establishments by preserving links with nodes which are in transmission range for a longer time and establish links with nodes which have more messages to transfer. The link preservation is based on estimation using past contact pattern with other nodes. The prediction of nodes that have more messages to transfer is based on the message hop list that contains nodes that have contributed to transfer the message. We evaluated our method by simulations. As a result, our proposal reduced message delivery latency by 40% at the early stage of elapsed time.