QoS Provisioning issues in Wireless Multimedia Sensor Networks

Increasing demand of imaging and video sensors in many applications of wireless sensor networks has led to the evolution of Wireless Multimedia Sensor Networks (WMSN). WMSN are wireless sensor networks that are able to retrieve multimedia content from the environment. WMSN applications require effective communication of event features in the form of multimedia such as audio, image, and video. The challenges faced in WMSN are same as Wireless Sensor Networks (WSN) but some additional challenges such as reliability, QoS, and high bandwidth demands, must be addressed as well. The main focus of research so far is on minimizing the energy consumption in WSNs, mechanisms to efficiently deliver application-level QoS, and to map these requirements to network-layer metrics such as latency and jitter, have not been primary concerns of research on sensor networks. Therefore, for fulfilling realtime requirements for multimedia delivery of data, new protocols need to be developed which not only ensure bounded response time but also strive to minimize energy consumption in data processing and communication. The QoS requirements in WMSN are quite different from traditional networks. In this paper we will discuss various QoS issues in network layer in WMSN and explain the reasons for the failure of traditional QoS models in WMSN. We review the work being carried out in provisioning QoS in WMSN followed by some open