Congratulations! Welcome to the world of Disruption Tolerant Networking. With a little help from this manual, and the DTN2 software, you'll soon be sending bundles to Mars and beyond.
The protocols that govern the way computers talk on the Internet largely assume that there are reliable low latency connections between any two points on the net. But several applications where we'd like to get the benefits of computer networking do not conform to that assumption. For instance, when NASA sends an instruction to a Mars Rover, there are both latency (speed of light delay) and disruption problems (no line of sight from Earth to Mars because the rover is on the back side of Mars right now, or it is the weather is bad at the receiving station). Another example is the challenge of getting the benefits of the Internet to a villiage in a developing nation. Traditional telecommunications technology cannot reach it cost-effectively, but a guy on a motorcycle can visit twenty such villages in a week much more cheaply than one could build a network to those twenty villages.
The Disruption Tolerant Networking (DTN) family of specifications and protocols lay out an architecture and mechanism to keep data moving even in the face of the difficulties these new environments present. For more information on DTN, visit the DTN Research Group web page. In particular, download and read Forrest Warthman's tutorial for a great introduction to all the concepts and terms in the DTN world.
DTN2 is the name for a reference implementation of the DTN protocols. It is designed as an experimental platform where researchers can validate the protocol designs, and do experiments to show that the DTN protocols are working as expected. For more information about DTN2's architecture and role as a platform for experimentation, see this paper by Michael Demmer and others.
Though DTN2 appeals to researchers, it is also intended to be high-quality, production-grade code ready for use in real world deployments. It has already been deployed to Cambodia and India as part of the TIER, Project, to Swedish Lapland as part of the N4C project, and we hope to see it deployed to many other environments that need to benefits of a DTN.
DTN2 primarily implements The DTN Bundle Protocol defined in the experimental specification RFC 5050. An RFC 5050-based DTN transmits data in the form of bundles that may be much larger than typical packets transmitted on IP networks. DTN2 also optionally supports the Bundle Security Protocol to provide authentication and/or integrity protection for transmitted bundles if required by the application. Bundles can be transmitted over either over (IP) transport layers or various link layers including Ethernet and Bluetooth. DTN2 implements a number of convergence layers that interface between the Bundle Protocol and the transports. DTN2 also provides a number of routing mechanisms to direct the forwarding of bundles to their intended destinations including a static routing scheme based on pre-configured routes and epidemic routing which floods bundles to any node it encounters.
We have ceased working on DTN1 in favor of DTN2, which has a significantly improved architecture for experimentation. DTN1 is still available from the DTN Research Group home page. You really should be using DTN2 for any new experiments or deployments.