Current networking protocols have been designed with the assumption that an end-to-end path between source and destination is almost always available. However, this assumption does not hold for an entire class of wireless networks. In Delay or Disruption Tolerant Networks (DTNs), lack of continuous connectivity, network partitioning, and very long delays are the norm, not the exception. Such networks have recently found applications in challenged environments, such as space communications, military operations, and sensor networks. Routing in DTNs is very challenging as it must handle the time-varying and unpredictable availability of links, long delays, and a dynamic topology.
This project contributes theoretical models and algorithms for routing in DTNs with semi-deterministic mobility. In such networks, node trajectory is either tightly controlled, but affected by random deviations from the environment, or it is socially driven. In both, opportunities for communication can be predicted using knowledge on node mobility. These networks, underrepresented by current research, have immediate applications in mobile sensing (e.g. littoral underwater monitoring), disaster management, or in campus environments. This research develops prediction models with Markov processes for node mobility and methods for contact probability estimation. Performance limitations and optimal parameters for the routing protocols and algorithms are also investigated. The research will produce a set of protocols suitable for operation in conditions of sporadic connectivity and limited resources, emphasizing local information exchange and adaptation techniques. The protocols will be evaluated with detailed simulations at the Florida Atlantic University Wireless and Sensor Network Laboratory.
