Improving Effective Contact Duration in Vehicular Delay-Tolerant Networks

Road safety and vehicle information applications may be jointly enhanced by IEEE 802.11 communications and Delay- and Disruption-Tolerant Networking, thus allowing for reliable and efficient communication in a highly mobile environment with frequent network disruptions and short inter-node contacts. Previous work on this topic has addressed several challenges of vehicular opportunistic communications such as routing and packet loss problems. In this paper we focus on the optimization of the throughput of opportunistic links. This throughput drops with the speed of moving vehicles because the effective communication interval is limited by the time the nodes lie within mutual radio range. We study how this effective communication interval is affected by possible modifications of the protocol stacks involved, and draw some useful conclusions about their practical application.