Wireless Packet Scheduling for Adaptive Service over IEEE802.11

Future wireless networks are expected to support multimedia applications. Wireless links, however, have scarce bandwidth compared to wirelines and should support host mobility. In addition to these characteristics, wireless networks have to deal with bandwidth variability and frequent packet errors due to multi-path fading and shadowing. Thus, providing more suitable wireless service is a great challenge. In this paper, we introduce the concept of adaptive service as a mobile service, which provides at least minimum tolerable quality over wireless networks. Adaptive service guarantees only minimum bandwidth with which minimum tolerable quality can be obtained, and shares the leftover bandwidth among the good-channel-state flows to improve the total throughput in a cell. We also present a wireless packet scheduling method to provide adaptive service and investigate its implementation method over the IEEE802.11 wireless LAN. Simulation results show that our scheduling method can meet the minimum bandwidth requirements and share the leftover bandwidth efficiently among the good-channel-state flows.