Cross-Layer Approaches to QoS Routing in Wireless Multihop Networks
This chapter addresses four types of multihop networks: wireless sensor network (WSN), mobile ad hoc network (MANET), wireless mesh network (WMN), and vehicular ad hoc network (VANET). It considers routing protocols that employ cross-layer design, which has become a fundamental design concept among wireless researchers. The chapter also considers quality of service (QoS) support from a broad perspective by reviewing several network types and the inherent challenges within each. The main metrics that most applications require for satisfactory performance are: Minimum Throughput, Maximum Delay, Maximum Delay Jitter, and Maximum Packet Loss Ratio. The performance of a routing protocol determined by directly measuring the QoS metrics required by the application, or through other means that can reflect how the protocol operates. Due to the high traffic demands, combining routing at the network layer with scheduling at the medium access control layer is a popular cross-layer approach in WMNs in order to avoid bottlenecks and ensure the desired QoS levels.