Since the IEEE 802.15.4 has been introduced and widely used as PHY/MAC layer for wireless mesh network and wireless personal area network(WPAN Mesh), the challenge of wireless mesh networks has been sifted to upper layer as traditional network architecture can not meet the requirements posted by wireless mesh networks. Although a lot of research efforts have been put into this area, there is still big gap between theoretical work and industry realization. The motivation of this thesis is to propose the solution that can leverage the real industry application capability of wireless mesh networks and provide the guideline to the next generation wireless mesh network design and implementation.
The topics of this thesis will address both networking and transportation layer challenges. First, we will present the IEEE 802.15.5, the industrial standard mainly developed by our lab which provides mesh capability for wireless personal area network (WPAN) devices. This thesis will focus on the low rate part of IEEE 802.15.5 which uses IEEE 802.15.4 as PHY/MAC standard. We will present the mandatory function design of IEEE 802.15.5, the contents include network formation, addressing scheme, link state information exchange and routing. Finally, the prototype implementation in the test-bed will be illustrated to demonstrate that the IEEE 802.15.5 will serve well for wireless personal area networks and wireless sensor networks.
The second part of thesis continue and enhance the works of IEEE 802.15.5, we further explore the fundamental capability of IEEE 8021.5.5 by providing a comprehensive analysis of IEEE 802.15.5. We will use four different performance metrics to calibrate the networking layer performance: scalability in view of memory space and energy consumption for routing establishment, fault tolerance represented by the node degree of next hop choices and Mean time to failure of routing path, routing path length compared with the shortest route, and the overhead associated with a mobility support. We will compare the performance of IEEE 802.15.5 with those of Zigbee PRO and the tree based scheme show the consistent superior performances of IEEE 802.15.5
The third part of thesis extends the IEEE 802.15.5 to address mobility case. We will first present the mobility support scheme in IEEE 802.15.5 and propose a distributed mobility support scheme for general wireless sensor networks. Evaluation is preformed and the results confirm the cost efficiency of proposed scheme.
The fourth part of thesis switch the focus to transportation layer, in which we target the most widely used TCP in wireless mesh network scenario. Instead of designing a new TCP algorithm customized to wireless mesh networks, we will propose Correlation-TCP, a TCP scheme based on TCP Newreno with an additional function which adjusts the TCP congestion window size based on correlation of congestion window size and RTT. The advantage of this new design lies in that the proposed TCP is compatible and fairly share bandwidth with current TCP algorithms in general wired Internets while has a much better performance in wireless mesh networks. Moreover, Correlation-TCP has the flexibility to meet various application layer requirements by tuning its parameters.
Final part of this thesis will conclude the thesis and provide future works.