Admission Control Based on Dynamic Rate Constraints in Multi-Hop Networks

This paper presents an admission control algorithm based on dynamic constraints for multi-hop networks. Assuming each node knows the topology and flow reservations within its radio range, local constraints on flow rates can be computed. As long as these constraints are satisfied, flows are accepted. Since computing optimal constraints is not practical, existing approaches compute a system of either necessary or sufficient constraints. In practice, the approach based on necessary constraints tends to overload the network whereas in the latter approach, a significant part of the bandwidth remains unused. In addition, these works assume that the interference model and the sublayers are optimal. In this paper, we propose to take into account the channel state in the constraints computation and, thus, to adjust them according to model relevance. Therefore we give a probabilistic model to evaluate the time spent by the channel in the idle state. By comparing this estimation with the measure value, we evaluate the model accuracy and include the corresponding error rate in the constraints of the admission control. Simulations show that our admission control algorithm outperforms previous work.