Neural bandwidth allocation function (NBAF) control scheme at WiMAX MAC layer interface

Abstract

AbstractThe paper proposes a bandwidth allocation scheme to be applied at the interface between upper layers (IP, in this paper) and Medium Access Control (MAC) layer over IEEE 802.16 protocol stack. The aim is to optimally tune the resource allocation to match objective QoS (Quality of Service) requirements. Traffic flows characterized by different performance requirements at the IP layer are conveyed to the IEEE 802.16 MAC layer. This process leads to the need for providing the necessary bandwidth at the MAC layer so that the traffic flow can receive the requested QoS.The proposed control algorithm is based on real measures processed by a neural network and it is studied within the framework of optimal bandwidth allocation and Call Admission Control in the presence of statistically heterogeneous flows. Specific implementation details are provided to match the application of the control algorithm by using the existing features of 802.16 request–grant protocol acting at MAC layer. The performance evaluation reported in the paper shows the quick reaction of the bandwidth allocation scheme to traffic variations and the advantage provided in the number of accepted calls. Copyright © 2006 John Wiley & Sons, Ltd.