Packet Scheduling for Bandwidth Sharing and Quality of Service Support in Wireless Local Area Networks

The growing deployment of wireless local area networks (WLANs) in corporate environments, the increasing number of wireless Internet service providers, and demand for quality of service support create a need for controlled sharing of wireless bandwidth. In this thesis, a method for using long-term channel-state information in order to control the sharing of wireless bandwidth is studied. The algorithm enables an operator of a WLAN to equalize the revenue/cost for each customer in the network and to control the link-sharing based on a combination of usercentric and operator-centric factors. As an example, we adapt one of the well-known wireline schedulers for hierarchical link-sharing, the Hierarchical Fair Service Curve Algorithm (H-FSC), for the wireless environment and demonstrate through simulations that the modified algorithm is able to improve the controlled sharing of the wireless link without requiring modifications to the Medium Access Control (MAC) layer. In addition, we present the design and implementation for a Linux based prototype. Measurements in a wireless testbed confirm that the scheduling scheme can perform resourcebased link-sharing on currently available hardware conforming to the IEEE 802.11 stan-