An Evaluation of Middleware Models with Focus on Constraints and Challenges in Wireless Sensor Networks

Wireless sensor networks (WSN) are long running distributed systems comprised of tiny devices called nodes. Nodes are capable of sensing, computing and communicating. These networks have been developed for wide range of applications including habitat monitoring, military surveillance, object tracking, building monitoring, smart offices and homes. WSN has many limitations that need to be taken into account, such as hardware constraints, limited energy, dynamic networks and unattended operations. These constraints raise the necessity of adopting a middleware. Various middleware architectures have been proposed so far to achieve suitable abstraction from underlying hardware and networks. They focus on ease of application development and maintenance of wireless sensor networks. These middlewares provide the capability to support and coordinate concurrent applications and act as a bridge between hardware, operating system, network stacks and applications. This thesis surveys some of the models and middlewares suggested so far. It evaluates the middlewares with focus on design challenges arise due to the distributed and resource constraint nature of the wireless sensor networks. It presents the comparison among various middlewares and addresses the differences as well as commonalities to find out the strengths and shortcomings in each model. This thesis shows that each middleware addresses only a limited subset of issues and design challenges. Each middleware or a group of middlewares, targets a specific set of issues based on the middleware’s own design based on the type of programming abstraction they provide. Keywords: Evaluation, Survey, Middleware, Middleware Models, WS