Active scheduling for programmable routers in open adaptive network environments

Abstract

Active and Programmable networks change the functionality of intermediate nodes by using agents and active packets. This paper presents a novel packet scheduling scheme called Active Scheduling to maintain QoS in virtual private networks (VPNs) within the domain of adaptive and programmable networks. In Active Scheduling agents on the router monitor the accumulated queuing delay for each service. In order to keep the end-to-end delay within the bounds, the weights for services are adjusted dynamically by agents on the routers spanning the VPN. If there is a rise or fall in queuing delay of a service, an agent on a downstream router informs the upstream routers to alter the weights of their queues. This keeps the end-to-end delay of services within the defined bounds and offers better QoS compared to VPNs using static WFQ. The paper describes Active Scheduling, and presents simulation results and these are compared with WFQ.