A stability-based link state updating mechanism for QoS routing

QoS routing, which satisfies diverse application requirements and optimizes network resource utilization, needs accurate link states to compute paths. Suitable link state update (LSU) algorithms which ensure timely propagation of link state information are thus critical. Since traffic fluctuation is one of the key reasons for link state uncertainty and existing approaches cannot effectively describe its statistical characteristics, we propose a novel stability-based (SB) LSU mechanism which consists of a second-moment-based triggering policy and a corresponding stability-based routing algorithm. They incorporate knowledge of link state stability in computing a stability measure for link metrics. With extensive simulations, we investigate the performance of the SB LSU mechanism and evaluate its effectiveness compared with existing approaches. Simulation results show that SB LSU can achieve good performance in terms of traffic rejection ratio, successful transmission ratio, efficient throughput and link state stability while maintaining a moderate volume of update traffic.