Quality of Service Support with Error Control Protocol in Wireless Local Area Networks

This dissertation discusses some techniques to improve the medium access control in infrastructure multi channel wireless local area networks. Medium Access Control protocols (MAC) coordinate the stations and resolve the channel contentions so that scarce radio resources are shared fairly and efficiently amongst participating users. We propose different models to improve the medium access control performance. The models deal with improving the channel access and allocation. By proposing some backoff strategies for the collided users to retransmit, the performance is improved. A comparison amongst the proposed models is shown.;We also investigate the quality of service provisioning in infrastructure-based wireless local area networks medium access control. We propose a multiple class traffic model to support quality of service. This model is a cross-layer model as we consider the error in the transmitted state. We also propose models for uplink channel utilizations for data channel transmissions that can be applied to different WLANs. Finally, we propose an integrated model that deals with error in both the request and data transmissions. That model applies in the single class and quality of service support models we develop.;In this dissertation, we propose four techniques to improve the medium access control frame utilization by developing four backoff strategies to reduce the collision on the request channels. We propose a cross-layer model for the error control protocol. We propose another model for uplink channel utilization for data transmission in one class of traffic. We also propose a quality of service support model so high priority users get better performance compared to low priority class traffic. Furthermore, we propose cross-layer design for data transmission to guarantee safe data delivery to the receiver for the QoS model. Finally, we propose a model for uplink channel utilization in the QoS model. This model can be applied to different WLANs standards. This model also includes the channel error in both the request and data channels.