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The heterogeneity of inter-contact time distributions: its importance for routing in delay tolerant networks

Vania Conan·Jeremie Leguay·Timur Friedman
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Abstract

Prior work on routing in delay tolerant networks (DTNs) has commonly made the assumption that each pair of nodes shares the same inter-contact time distribution as every other pair. The main argument in this paper is that researchers should also be looking at heterogeneous inter-contact time distributions. We demonstrate the presence of such heterogeneity in the often-used Dartmouth Wi-Fi data set. We also show that DTN routing can benefit from knowing these distributions. We first introduce a new stochastic model focusing on the inter-contact time distributions between all pairs of nodes, which we validate on real connectivity patterns. We then analytically derive the mean delivery time for a bundle of information traversing the network for simple single copy routing schemes. The purpose is to examine the theoretic impact of heterogeneous inter-contact time distributions. Finally, we show that we can exploit this user diversity to improve routing performance.

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Vania Conan, Jeremie Leguay, Timur Friedman. 2007-01-05. The heterogeneity of inter-contact time distributions: its importance for routing in delay tolerant networks. https://arxiv.org/abs/cs/0609068

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