Formulation of a New Constraint for Admitting Flows in Multi-Rate Wireless Ad Hoc Networks

Admission and rate control are key components for providing QoS (Quality of Service) flows in multi-rate wireless ad hoc networks where transmission rate at the physical layer is adapted dynamically according to the channel condition. Key to these controls is the formulation of a rate constraint that can regulate the flow rate passing through each node. This paper formulates a cross-layer rate constraint to serve this purpose. Although node-based, the new rate constraint captures the interference level at the receiver side as well as the contention at the sender side, which is more accurate than that of existed work. Simulation results on DSR incorporated with such constraint show that the QoS routing algorithm can admit feasible flows and make full use of the bandwidth resource based on the rate constraint, moreover it outperforms the other algorithms in the scenarios we tested.