Quality of Service Support in Wireless Ad Hoc Networks Connected to Fixed DiffServ Domains

This paper analyzes the provision of end-to-end Quality of Service between nodes in a mobile ad hoc network and a fixed IP network that supports Differentiated Services. The ad hoc network incorporates the Stateless Wireless Ad Hoc Networks (SWAN) model to perform admission control for real-time traffic flows. We propose a new protocol, named DS-SWAN (Differentiated Services-SWAN), where end-to-end delays and loss rates of real-time traffic are monitored continuously at the destination nodes in the fixed network and at the edge routers respectively. In this way, nodes in the ad hoc network are warned when congestion is excessive for the correct functioning of a real-time application (specifically, Variable Bit Rate Voice-over-IP), so that the nodes restrain best-effort traffic in order to favour real-time flows. The results indicate that DS-SWAN significantly improves end-to-end delays without starvation of background traffic, adapting itself to changing traffic and network conditions in a relatively small ad hoc network. Besides, we compare different notification procedures in DS-SWAN aimed to improve scalability.