You are presented with multiple paper abstracts, alongside the associated literature review and chapter titles. Given the provided information, you are going to do a literature review. Please generate a coherent literature review that synthesizes the content, draws connections between different works, highlights major findings, and identifies any gaps in the existing research.

Literature Review Title: Survey of QoS routing protocols in Wireless Multimedia Sensor Networks 
Chapter Title:  Multiconstraint QoS. 
1. Abstract of Cited Paper (BIB001):  A wireless sensor network is a large collection of sensor nodes with limited power supply and constrained computational capability. Due to the restricted communication range and high density of sensor nodes, packet forwarding in sensor networks is usually performed through multi-hop data transmission. Therefore, routing in wireless sensor networks has been considered an important field of research over the past decade. Nowadays, multipath routing approach is widely used in wireless sensor networks to improve network performance through efficient utilization of available network resources. Accordingly, the main aim of this survey is to present the concept of the multipath routing approach and its fundamental challenges, as well as the basic motivations for utilizing this technique in wireless sensor networks. In addition, we present a comprehensive taxonomy on the existing multipath routing protocols, which are especially designed for wireless sensor networks. We highlight the primary motivation behind the development of each protocol category and explain the operation of different protocols in detail, with emphasis on their advantages and disadvantages. Furthermore, this paper compares and summarizes the state-of-the-art multipath routing techniques from the network application point of view. Finally, we identify open issues for further research in the development of multipath routing protocols for wireless sensor networks. 
2. Abstract of Cited Paper (BIB002):  Wireless Sensor Networks (WSNs) have enjoyed dramatic developments over the last decade. The availability of CMOS cameras and microphones enlarged the scope of WSNs paving the way to the development of Wireless Multimedia Sensor Networks (WMSN). Among the envisaged WMSN applications, Real-time Multimedia Monitoring constitutes one of the most promising. However, the resource requirements of these applications place difficult challenges in terms of network lifetime and scalability. This paper starts by identifying the main characteristics and requirements of Real-time Multimedia Monitoring applications and then highlights key research directions that may help to overcome those challenges. 
3. Abstract of Cited Paper (BIB003):  The emergence of wireless multimedia sensor networks (WMSN) has given birth to several civilian as well as defense applications. Some of the interesting applications employing low cost sensor nodes to manipulate rich multimedia content include traffic monitoring, border surveillance, smart homes, environment and habitat monitoring. Unlike the traditional sensor networks which are aimed at maximizing network lifetime by decreasing energy utilization, the main objective of WMSNs is optimized delivery of multimedia content along with energy efficiency. Multimedia communications in WMSNs, has stringent delay and high bandwidth requirement as compared to scalar data transfer in WSNs. Fulfilling these constraints in resource and energy constrained WMSNs is a huge challenge. In WMSNs, each layer of the protocol stack is responsible and fully involved in providing QoS guarantees. There is a need for new schemes at each layer of the protocol stack- from advanced coding techniques that reduce encoder complexity and achieve maximum compression to dynamic routing and MAC protocols that provide service differentiation and reduce end-to-end latency. In wireless sensor networks, where all layers have dependency on each other, QoS guarantees are possible through the cross layer interaction of different layers. This paper gives an overview of the different existing layered schemes in WMSNs, followed by a discussion on the significance and efficiency gains that can be achieved from cross layer interactions in WMSNs along with the review of the existing cross layer approaches. Finally, we identify the open research issues which have not been adequately addressed so far.

Literature Review:
Multimedia data traffic has diverse QoS requirements. Thus, there is a need to design a mechanism to deliver multimedia data with a certain level of QoS. These QoS parameters include throughput, bandwidth consumption, energy efficiency, reliability, delay (latency), jitter, mobility, and security. Multiconstraint routing protocol should ensure that delay remains within an acceptable range, and the link bandwidth pertains to the average compression ratio, average jitter, and less energy consumption. For example, in Figure 2 , multiconstraint QoS profile emphasizes reliability, throughput, and energy efficiency. Considerable development in multiconstraint-based routing has been achieved to date. Most of this work considers a maximum of three to four constraints for optimizing the performance of routing protocols. A more holistic approach based on multiconstraint QoS is open for exploration in WMSNs BIB001  BIB002 BIB004 BIB003 .