Traditional networks, both wired and wireless, have the property that end-to-end paths between nodes are relatively stable. However, not all environments that require communication will allow the creation of stable end-to-end paths. For example, the aftermath of a severe earthquake disaster will include collapsed buildings, persons trapped in debris, damaged utilities and roads, as well as fires and secondary explosions. Under this situation, the ability to communicate, even at low rates, is extremely valuable for sharing vital information, such as the number and location of survivors and the activities of rescue workers. To provide communication in these challenged environments, the network protocols must be explicitly designed to perform despite frequent disruptions in the availability and performance of network components (i.e., links and nodes). The resulting systems are termed Disruption Tolerant Networks (DTNs).
This work focuses on the construction of DTNs that go far beyond the task of finding unicast paths. Instead, these DTNs are robust under uncertainty and attack, and are highly efficient in their use of the node and link resources. Specifically, this project focuses on the following fundamental functions: group communication, single-hop transfers, and power management. The work is grounded by experimentation in testbeds at the collaborating universities. The project provides algorithms, protocols, and platforms to create robust and efficient DTNs enabling communication in the most critical of environments, as well as exposes cost-performance tradeoffs that might have broader applicability in less challenged networks.
