Performance analysis of message prioritization in delay tolerant networks

A variety of network deployments in disaster recovery, fire fighting and military scenarios create networks that do not form a connected network all the time. In such scenarios, paths between a source and destination may be created over time when nodes encounter each other due to node mobility. Many routing algorithms that can route messages in such delay-tolerant networking (DTN) settings have been proposed. Currently, these protocols do not differentiate between the messages that are being routed through the network treating all messages equally. But, there are DTN scenarios, in particular in military situations, where it is critical that messages are differentiated based on their importance to the task being supported. In this paper, we propose extensions to two popular DTN routing protocols, Epidemic and PROPHET, to implement such message prioritization. We implemented the proposed extensions in ONE (Opportunistic Network Emulator) and studied the performance of these extensions. Results from our simulation analysis demonstrate that it is possible to implement message prioritization in non-deterministic delay tolerant networks and provide us with insights into configuring message prioritization in DTN. In particular, the importance of selecting optimal queue lengths at each node to mitigate congestion in such networks.