On end-to-end performance of multi-service concatenation

Channel scheduling algorithms that are used in network routers play a vital role in providing end-to-end quality of service(QoS) guarantees. In a heterogeneous network environment, a mixture of scheduling schemes is often found at the various routers. Although weighted fair queueing(WFQ), when combined with traffic policing, has been regarded as an ideal scheduling scheme in terms of its end-to-end delay bound and fairness properties, its asymptotic time complexity increases linearly with the number of flows serviced by the scheduler, thus is still considered an expensive scheduling scheme. First-come-first-serve(FCFS), on the other hand, lacks fairness property but is simple to implement. A network model is developed to investigate the end-to-end performance of a data flow path that is comprised of network elements using different scheduling disciplines. Results from simulation are reported and discussed.