Medium access control protocols and routing strategies for wireless local and personal area networks

Recent advances in portable computing and wireless technologies are opening up exciting possibilities for the future of wireless mobile networking. More notably, Wireless Local and Personal Area Networks (WLANs and WPANs) technologies are expected to revolutionize the way we live. Given their unprecedented importance, in this dissertation we investigate and suggest new solutions in the context of WLANs and WPANs systems. In the world of WLANs, we study its major representative, namely, the IEEE standard 802.11, while we explore the Bluetooth technology as it is the most prominent solution in the world of WPANs. In the field of Bluetooth, we have identified key issues and made considerable contributions. We have carried out a detailed analytical and simulation analysis of radio interference impact on Bluetooth and proposed ways of mitigating it, such as a novel interference-aware packet segmentation protocol (IBLUES). Moreover, we also introduce an integrated IEEE 802.11 and Bluetooth architecture (BlueStar), which enables efficient information interchange between these two widely used technologies. BlueStar is analyzed in great detail and, among other things, it features a new coexistence method between IEEE 802.11 and Bluetooth which employs a novel combination of carrier sense and adaptive frequency hopping. Next, to handle the inefficiency of the current Bluetooth master/slave communication paradigm, we propose a novel QoS-driven dynamic slot assignment and piconet partitioning algorithms. In the context of IEEE 802.11, we initially investigate advanced MAC-based routing strategies. These strategies, referred to as COPAS (contention-based path selection), are intentionally devised and observed to boost TCP performance over the multi-hop type of IEEE 802.11 ad hoc networks, given that TCP is by far the most important and widely used transport protocol in today's networks. Finally, we design and evaluate a new power control MAC protocol for spatial reusability over ad hoc networks, which is observed to considerably outperform existing MAC protocols. We conclude with some promising future work in the areas of both Bluetooth and IEEE 802.11.