QoS routing in mobile ad hoc networks based on the enhanced distributed coordination function

This paper proposes a QoS routing protocol (RP) for multimedia services in mobile ad hoc networks (MANETs). We adopt a new distributed MAC protocol, called enhanced distributed coordination function (EDCF), to support service differentiation. It requires a QoS RP to find routes with QoS guarantees. The proposed QoS RP discovers routes for source-destination transmission pairs with bandwidth and end-to-end delay guarantees. The procedures of neighborhood maintenance, QoS violation detection, and route maintenance are also presented in this paper. Furthermore, we introduce a new problem called hidden route problem, which arises because of existing routes that are hidden from the current route discovery procedure. This problem is also solved in the proposed QoS RP. We use the ns-2 simulation to evaluate the performance of the proposed QoS RP and compare it with other ad hoc QoS RPs. Simulation results show that the performance criteria, such as packet delivery ratio and average end-to-end delay, outperform other existing QoS RPs with the sacrifice of routing overhead under light load conditions.