Disruption Tolerant Networks (DTNs) require routing algorithms that are different from those designed for ad hoc networks. In DTNs, transport of data through the network is achieved through the physical movement of the participants in the network. We address two fundamental problems of routing in DTNs: routing algorithms with robust delivery rates, and management of networks where demand for routes does not match with the movement of peers. For the first problem, we propose the MV algorithm, which is based on observed meetings between peers and visits of peers to geographic locations. We show that our approach can achieve robust delivery rates: 83% of the maximum possible delivery rate, as compared to 64% for fifo buffer management. The advantage remains significant as the offered load of the system is increased an order of magnitude. For the second problem, we propose to augment available routes and capacity in a DTN through autonomous agents (e.g., autonomous blimps or mobile robots). We propose a controller that moves the agent to where network needs are not being met by the movement of peers. Our controller is able to increase delivery between fifteen and twenty-five percent. Our experiments shows that the introduction of even a few agents can dramatically increase the reliability of the message ferrying network. Moreover, our techniques are compatible and offer a robust method of approaching the problems of DTNs.
Available at: http://works.bepress.com/oliver_brock/2/