Quality-of-Service Analysis of Queuing Systems with Long-Range-Dependent Network Traffic and Variable Service Capacity

Many high-quality measurement studies have demonstrated that wireless network traffic exhibits the noticeable Long-Range-Dependent (LRD) property. Moreover, the fading nature of wireless channels can lead to variable service capacity. Due to the inherent difficulty and high complexity of modelling the fractal-like LRD traffic, existing analytical models of queuing systems with LRD arrival processes have been primarily limited to the simplified scenarios where the service capacity is assumed to be constant. Given the time-varying nature of wireless channels in the real-world working environments, it is very important and necessary to investigate system performance in the presence of variable service capacity. To this end, this paper presents a comprehensive analytical model for queuing systems subject to LRD traffic and variable service capacity. We extend the application of a Large Deviation Principle and derive the closed-form expressions of Quality-of-Service (QoS) metrics. The accuracy of the model validated through extensive simulation experiments makes it a cost-effective evaluation tool for performance analysis of communication networks. To illustrate its applications, the model is adopted to investigate the effects of LRD traffic and variable service capacity on the system performance and resource configuration.