Programming Disconnected Operations in Wireless Sensor Networks

Abstract: Wireless sensor networks, networks of nodes communicating wirelessly with sensing capabilities, are becoming more popular and are utilized by an increasing number of applications. Some wireless sensor networks are implemented because the usual network solutions of an always connected network could not be applied. Specifically this thesis is concerned with the case when the connection between the end-user and the network is not always available, i.e., there is only intermittent connectivity. This masters thesis gives an introduction and provides some background knowledge concerning wireless sensor networks, specifically focusing on disconnected operation. A set of building blocks will be presented to help programmers deal with programming disconnected operations. Examples to demonstrate our solution is implemented as shell commands using the Contiki operating system. Our solution was tested in the field and compared against a common, monolithic, programming approach. This practical example shows the potential significance of this thesis project in real world applications and allowed an evaluation of both the qualitative and quantitative aspects of our solution. The results of our evaluation prove that our solution offers an easier interface for the programmer to work with at the cost of possible less memory space.