A system theoretic approach to the design of an admission controller for high-speed networks

Abstract

This paper presents a novel real-time discrete-event admission control (AC) scheme with a desired quality of service (QoS) guarantee and that results in high network utilization in high-speed networks is proposed. The AC uses the following information: the available capacity from a novel adaptive bandwidth estimation scheme, a congestion indicator derived from a congestion controller, Peak bit/cell Rate (PBR/PCR) estimate from new sources, along with the desired QoS metrics, and outputs an 'admit' or 'reject' decision signal to the new sources while guaranteeing QoS and network utilization. The dynamics of the admission controller is expressed as discrete-event system while the bandwidth estimator and the congestion controller dynamics are in discrete-time. The overall stability of the congestion plus the admission controllers is shown using hybrid system theory. The performance of the proposed AC is evaluated based on the predefined QoS metrics and network utilization. Simulation results are presented by streaming ON/OFF and video data into the network. Results show that the proposed AC admits significantly more traffic compared to other available admission control schemes thereby guaranteeing high network utilization while maintaining the desired QoS.