This thesis explores how usability in delay- and disruption tolerant network (DTN) applications might be developed and how DTN applications services might be put to practical use in remote regions of the Swedish Arctic. The tangible results presented are a set of end-user DTN application services that were developed for the remote sites Saltoluokta and Staloluokta.Challenges that have created the need for new technology include topology, climate, lack of electrical infrastructure and lack of cellular coverage. DTN research aims to make data communication possible where communication is otherwise difficult, using state-of-the-art routing protocols and algorithms. Just as in a “legacy” Internet application, a DTN application is created to transfer information between nodes in a network: text, images, video, sound etc. Applications can be implemented in a network to perform a certain task, whether it be automated or user-generated data.The main challenge with Arctic DTN applications is in the combination of technical and environmental contexts. The development of the applications presented in this thesis took place in the multi-disciplinary N4C project 2008 to 2011. The research team faced challenges that included how to make prototypes of the application services usable enough for the nomadic population in the Sami villages of Tuorpon and Sirges, in Padjelanta and Sarek national parks.The thesis presents an assessment of the developed application services, with technical specifications and tries to answer what usability in DTN applications is, how it can be evaluated and when an application can be deemed usable. The theories of Human-Computer Interaction (HCI) and a reference to this field’s history can explain the development of the DTN web applications as part of the history of technical development of information technology artifacts and their application in daily life. Since DTN “real life” applications are new, and the technology behind them is still in an early stage of development, it is not possible to point to any given evaluation method for usability assessment.While an “only HCI” strategy would suffice to create good DTN services, some important aspects could be missed, for instance, the ties to democratic values and the overall socio-technical environment. In the work presented HCI theory meshes with Participatory Research and the Software Engineering process. The development of the prototype applications was an iterative process. The conclusion is that when participants see a benefit in using the services, this is acceptable usability.

Many locations are not within reach for the physical infrastructure of communications networks. This is a challenge for the Future Internet. One technology currently investigated as a possible enabler is Delay Tolerant Networking (DTN). It is a reasonable assumption that the applications that are the presently most used in the "normal" internet will continue to be of most importance also in hitherto not ICT covered areas. But, for local SMEs the rational may rather be development of specialized services, exploiting DTN technology to increase the efficiency and market potentials for their activities in remote locations. To achieve this, hardware and open source software are put together to form a node system that make up the DTN applications, custom built to the situation with focus on power management, routing schemes and custom made software based on user need. These nodes are tested with users in real life test beds, enabling internet connectivity to reach even further, without the need for new physical infrastructure.