Analytical Framework for Contact Time Evaluation in Delay-Tolerant Networks

In the last few years, there has been an increasing concern about stochastic properties of contact-based metrics under general mobility models in delay-tolerant networks. Such a concern will provide a first step toward detailed performance analysis of various routing/forwarding algorithms and shed light on better design of network protocols under realistic mobility patterns. However, throughout the variety of research works in this topic, most interests rather focused on the inter-contact time while other contact-based metrics such as the contact time received too little interest. In this paper, we provide an analytical framework to estimate the contact time in delay-tolerant networks based on some recent key results derived from biology and statistical physics while studying spontaneous displacement of insects such as ants. In particular, we analytically derive a closed-form expression for the average value of the contact time under the random waypoint mobility model and then give an approximation for its distribution function.