Implementing Delay Tolerant Networking

The recently proposed Delay Tolerant Networking (DTN) architecture aims at supporting efficient messagebased communication over intermittent networks. This paper describes our experience in creating and evaluating a DTN reference implementation. We found that several concepts are not fully specified in the DTN literature, including the treatment of mobile and opportunistic contacts and the grouping of nodes into regions. Given the novelty and challenges inherent in DTN routing, the implementation includes a custom internal interface to the route selection and message forwarding components that eases development of new algorithms. We verify the implementation with an Emulab-based performance evaluation of the DTN store-and-forward approach as compared with traditional Internet-style data transfer methodologies, and a demonstration of an epidemic routing protocol. We found that in many “challenged” environments, the deployment of DTN systems can result in significant performance gains over other approaches.