An epidemic broadcasting mechanism in delay/disruption-tolerant networks utilizing contact duration distribution

Epidemic broadcasting, in which an infected node repeatedly forwards a copy of a message to other nodes, realizes one-to-many communication in delay/disruption-tolerant networks. In epidemic broadcasting, the key is to control the number of message forwardings among nodes while maintaining a short message delivery time in the network. In this paper, we present a novel idea for improving the performance of epidemic broadcasting: when an infected node encounters a (possibly) susceptible node, the infected node intentionally delays its message forwarding since this may increase the chance of simultaneous transmission to multiple susceptible nodes. On the basis of this idea, we propose HCD-BCAST (History-based Contact Duration aware BroadCAST), which significantly reduces the number of message forwardings. In HCD-BCAST, each node autonomously determines the message forwarding delay based on the contact duration distribution measured by that node. Through simulations, we show that HCD-BCAST achieves a reduction of approximately 10-40% in the number of message forwardings compared with history-based self-adaptive broadcast and k-neighbor broadcast.