Utility-Based Enhanced Priority Scheduler for Differentiated Services

Abstract

Differentiated services (DiffServ) is a QoS architecture that seeks to provide service differentiation to a small number of service classes. Priority queuing (PRIQ), a scheduling mechanism that provides a fixed number of priority levels to different service classes, can be used for DiffServ provisioning. However, it has the inherent problem of starvation in the lower priority classes. A new framework, value-based utility (VBU), models the perceived knowledge of the state and degree of user satisfaction in managing router resources and functions. We propose the use of the VBU framework to improve the PRIQ mechanism. We designed and implemented an enhanced PRIQ mechanism which uses packet remarking on an ALTQ router. Our results show that our mechanism effectively improves the performance in the low priority class while maintaining the QoS guarantees of the higher priority classes