Packet Scheduling Algorithms for QoS in Next Generation Routers

Packet Scheduling Algorithms for QoS in Next Generation Routers

Abstract

Real Time communications over Internet require Quality of Service guarantees. On the other hand, the conventional best effort traffic requires fair allocation of resources. Fair queueing algorithms were developed to address the issue of providing fairness to TCP flows. In this talk, we provide an overview of fair packet scheduling algorithms. We then discuss the issue of providing Quality of Service guarantees. If the traffic is leaky bucket regulated, then it can be shown that fair queueing algorithms can be also used to provide delay guarantees. We review the theory of Latency Rate servers which can be used to derive the worst case delays achievable by packet scheduling algorithm. We also address the issue of delay bandwidth coupling and suggest a modification to scheduling algorithm. We conculde the talk by identifying the issue of scalability of packet scheduling algorithms and differentiated services architecture for next generation Internet.