On utility-fair adaptive services in wireless networks

Adaptive quality of service techniques can effectively respond to time-varying channel conditions found in wireless networks. In this paper we assess the state-of-the-art in quality of service adaptive wireless systems and argue for new adaptation techniques that are better suited to respond to application specific adaptation needs. A quality of service adaptive data link control model is presented that accounts for application specific adaptation dynamics that include adaptation time-scales and adaptation policies. A centralized adaptation controller employs a novel utility-fair allocation scheme that supports the dynamic bandwidth needs of adaptive flows over a range of operating conditions. Three wireless service classes play an integral role in accommodating a wide variety of adaptation strategies. In this paper, we discuss the design of the utility-fair bandwidth allocation scheme and the interaction between the centralized adaptation controller and a set of distributed adaptation handlers, which play a key role in intelligently responding to time-varying channel capacity experienced over the air-interface.