Queue Management and QoS Routing for Traffic Differentiation

Authors

Abstract

This paper presents a simulation study of router mechanisms to provide differentiated levels of service to traffic with diverse performance requirements in IP networks. The paper focuses on queue management mechanisms and on Quality of Service routing. In what concerns queue management the performance of the Random Early detection dropper associated with the Weighted Round Robin scheduling discipline is compared with the Dynamic Degradation Distribution system. Besides doing traffic differentiation using scheduling and dropping mechanisms, the Dynamic Degradation Distribution system redistributes the resources among the traffic classes according to the state of the interface of the router created by the current traffic mix. Afterwards, the impact of Quality of Service routing in networks where there is class-based traffic differentiation is assessed. The results show that even though the queue management mechanisms actually deployed in commercial routers naturally support traffic differentiation and provide adequate levels of Quality of service, the Dynamic Degradation Distribution system is able to give better performance in situations of congestion. Moreover, the inclusion of Quality of Service routing capabilities clearly improves traffic performance and network utilization.

Subject

QoS routing

Related Project

IPQoS - Study of QoS Mechanisms for IP Routers