Because wireless sensor networks (WSNs) are complex and difficult to deploy and manage, appropriate structures are required to make these networks more flexible. In this paper, a reconfigurable testbed is presented, which supports dynamic protocol switching by creating a novel architecture and experiments with several different protocols. The separation of the control and data planes in this testbed means that routing configuration and data transmission are independent. A programmable flow table provides the testbed with the ability to switch protocols dynamically. We experiment on various aspects of the testbed to analyze its functionality and performance. The results demonstrate that sensors in the testbed are easy to manage and can support multiple protocols. We then raise some important issues that should be investigated in future work concerning the testbed.

The routing layer quality of service in wireless sensor network depends on different indices such as throughput, delay, packet loss rate, energy consumption, and degree of congestion. A single index does not adequately reflect the real quality of service while an excessive number of indices increase the complexity of the evaluation model. In addition, existing quantitative evaluation methods can lead to under-fitting or over-fitting. In this article, we present a comprehensive qualitative quality-of-service evaluation method based on the cloud model. Using Gaussian cloud transformation, each quality-of-service index can be divided into several qualitative concepts (cloud models). Concepts belonging to different indices can be combined together to evaluate the quality of service. We use a frequent-pattern tree approach to mine association rules of quality-of-service concepts and arrive at a suitable decision. This method simplifies the evaluation model by transforming a numeric value to its equivalent qualitative concept and brings out the internal relationships among different quality-of-service indices according to the association rules. Besides, it automatically finds a common standard to evaluate and compare different routing protocols simultaneously. The evaluation results show that the proposed method provides a good quality-of-service assessment when applied to different routing protocols.