Scheduling Algorithm And Cross-layer Protocol Reference Model In Multi-hop Wireless Networks

Because of frequently changing channel and user mobility in multi-hop wireless ad hoc networks, the original TCP is no longer suitable for such kind of networks, and many new protocols and architectures have been proposed to improve network performance. Among them, cross-layer design is considered to be an effective way, but there is not a general protocol reference model available so far. Therefore, it is necessary to study protocol reference models for cross-layer design.On the other hand, different applications have different quality of service (QoS) requirements such as packet delays and loss rates so that provisioning of more granular QoS for different applications in multi-hop wireless networks is another challenge issue. However, most traditional scheduling algorithms mainly use local information without considering the whole network. To take into account the end-to-end situation, cross-layer design may be required to obtain more information for more accurate and more effective scheduling.The major contribution of this thesis contains the following two parts. First, a cross-layer protocol reference model design using shared database, and its implementation in Network Simulator. This model has an explicit structure, with which a protocol layer can access the information of other layers through a general interface. Second, an implementation of the DQS algorithm in the above mentioned cross-layer reference model is carried out with Network Simulator along with the performance investigation of this implementation in multi-hop wireless networks. The simulation results show that the performance of DQS is better than that of EDF (early-deadline first) in terms of average goodput and end-to-end delay.