New adaptive protocols for fine-level end-to-end rate control in wireless networks

Abstract

Fine-level rate control, particularly meeting rate requirements and differentiating various types of end-to-end traffic, remains an open problem for multihop wireless networks. Traditionally, rate assurance in wired networks is achieved through resource reservation and admission control, which can be efficiently implemented since the bandwidth capacity of each communication link is known and the sender of a link has the information of all flows that compete for the bandwidth of the link. In a wireless network, however, the capacity of each wireless link can change unpredictably over time due to contention from nearby links and dynamic channel conditions. An end-to-end flow consumes available bandwidth not only at links on its route but also at all nearby contending links, which makes resource reservation extremely complicated. We believe fundamental differences require a fundamentally different paradigm shift in solutions. Is there a simpler alternative to resource reservation and admission control that is better suited for wireless network dynamics? In this paper, we propose a new adaptive rate control function based on two novel protocols, called dynamic weight adaptation with floor and ceiling and proportional packet scheduling, which together implement prioritized rate assurance and sophisticated bandwidth differentiation among all end-to-end flows in a multihop wireless network without resource reservation and admission control. The adaptive function achieves global rate control objectives in a fully distributed way using only localized operations.