## 1 Introduction  
Even though many typical Wireless Sensor Networks (WSNs) have been employed to detect the events and report interested values around itself, they are typically based on scalar values and therefore have limited abilities to obtain various types of information. This implies that limited information, such as the geographic position of the target, can be recorded. As an alternative, wireless multimedia sensor networks (WMSN) [1] can capture multimedia information about the object or event by using a camera and microphone. However, the more complicated nature of multimedia data (compared to scalar values) has prompted considerable research in an attempt to effectively capture the information as well as to deliver this information in real time. One of the good potential examples of WMSN is industrial sensor networks [2] to monitor and control systems. In industrial sensor networks, it is essential to employ QoS routing protocol in WMSN to accomplish the mission. To address the problems associated with real-time delivery in WMSNs, several quality of service (QoS) routing protocols [3; 4; 5] have been proposed and discussed in the literature. However, most existing schemes still need to be improved by using a specific traffic model and applications. Based on general application model, many of them lack of applicability and lead to failure of QoS guarantee. To defeat this problem, the (\(m\),\(k\))-firm traffic model was recently presented for WMSNs. As a firm real-time model called (\(m\),\(k\))-firm is proposed to measure real-time application performance. The concept of (\(m\),\(k\))-firm is defined that a real-time message stream is considered to have an (\(m\),\(k\))-firm guarantee requirement that at least \(m\) out any \(k\) consecutive messages from the stream must meet their deadlines to ensure adequate QoS. However, the (\(m\),\(k\))-firm model has not been studied with respect to finding specific applications in which this model could be utilized. Thus, they have the same problem as general QoS routing protocol. These issues motivated us to develop the adaptive real-time routing protocol we present in this paper. The model is based on the (\(m\),\(k\))-firm model [6; 7], which serves the purpose of adding real-time capabilities. Unlike previous work, which focused on real-time delivery only, our previous approach is to introduce a multimedia application modeled by a (\(m\),\(k\))-firm stream. This new stream is maintained to ensure quality by using a new QoS routing protocol for the (\(m\),\(k\))-firm stream to reduce the overhead for path establishment and maintenance. To achieve this goal, based on the current status of application of the (\(m\),\(k\))-firm stream, a new QoS routing protocol was designed to select the path adaptively. When this routing protocol is unable to meet the requirement, an adaptive traffic-handling algorithm is employed. The operations of these two functions, which are dependent on the current status of the (\(m\),\(k\))-firm streams, ensure that high adaptability is achieved. Finally, extensive simulation results show that the proposed scheme meets the requirements of the (\(m\),\(k\))-firm stream for application and also provides robustness in terms of network traffic. The main contributions of this paper are summarized below. * To recognize the shortcomings or limitations of QoS routing protocol in WMSN, we provide a comprehensive survey that investigates state-of-the-art research work and further research directions for applying application specific requirement to the QoS routing protocol. * To overcome the problem of general routing protocol considering deadline, we take (\(m\),\(k\))-firm based routing protocol while considering application requirements which is modeled by (\(m\),\(k\))-firm stream together. * Unlike most of existing approaches which are based on (\(m\),\(k\))-firm stream, we propose a new adaptive path selection and traffic shaping algorithm. * The proposed scheme is compared to existing (\(m\),\(k\))-firm based QoS routing protocols.