A new coordinated scheduling algorithm in distributed bandwidth broker QoS architecture

Providing quality of service (QoS) is a critical issue in the current Internet. Recently, many distributed bandwidth broker architectures have been proposed for scalable QoS provision. One important task of bandwidth brokers is admission control, which decides whether a new data flow can be admitted without violating the QoS requirements of other existing data flows. In distributed bandwidth broker architectures, an admission control request needs to be processed by all bandwidth brokers on its path. Thus it is important for bandwidth brokers to schedule the processing of requests properly so that as many as possible requests can be processed within setup latency bounds. Most existing end-to-end delay-guarantee scheduling schemes depend on bandwidth reservation, traffic characterization, or priorities, which are not applicable to the scheduling of control plane requests. In this paper, we propose a new multi-hop coordinated scheduling algorithm P-EDF to improve the throughput of the admission control requests that are processed within setup latency bounds in distributed bandwidth broker architectures. Simulation results show that the P-EDF scheduling algorithm can achieve 20∼30% higher throughput in request processing than other existing scheduling algorithms in distributed bandwidth broker architectures.