A Middleware Layer Mechanism for QoS Support in Wireless Sensor Networks

Wireless sensor networks need different satisfying Quality of Service (QoS) levels for their successful operation. Providing QoS support for wireless sensor networks at the middleware layer is a new research area. This paper proposes a real-time and faulttolerant mechanism as a middleware for wireless sensor networks which operates according to sensor nodes' requirements like data rate and energy. A service-based middleware receives users' QoS requirements about wireless sensor networks' services and guarantees time critical responses in an efficient and scalable way in a cluster-based organization. The proposed mechanism can support multiple sink nodes' QoS requirements and can utilize the redundancy of wireless sensor networks, especially multiple service providers to guarantee fault tolerance. It uses local information to schedule critical messages, and monitors nodes in an energy efficient way. Evaluation results show that the cost of real-time support is nearly low and can meet real-time requirements.