Performance analysis of a single-server ATM queue with a priority scheduling

Abstract

Scope and purposeQueueing theory is an important subject in computers and operations research. Buffers/queues are used, e.g. in telecommunication networks, to store information that cannot be transmitted instantaneously. The study of the buffer behavior is important since network performance is directly related to it. Queues with a priority scheduling discipline are an important subject in queueing theory. As a result, these type of queues are thoroughly studied in the past, especially in continuous time. In discrete-time queueing models on the other hand, this type of queues is not as widely studied. Discrete-time queueing models are suitable for the performance evaluation of Asynchronous Transfer Mode (ATM) switches. In ATM, different types of traffic need different Quality of Service (QoS) standards. The delay characteristics of delay-sensitive traffic (e.g., voice) are more stringent than those of delay-insensitive traffic (e.g., data). We can thus give priority to delay-sensitive traffic over delay-insensitive traffic, thus trying to reduce the * Corresponding author 1 delay of the delay-sensitive traffic. This paper studies the impact of a priority scheduling on the buffer characteristics. AbstractIn this paper, we consider a discrete-time queueing system with head-of-line (HOL) priority. First, we will give some general results on a GI-1-1 queue with priority scheduling. In particular, we will derive expressions for the Probability Generating Function of the system contents and the cell delay. Some performance measures (such as mean, variance and approximate tail distributions) of these quantities will be derived, and used to illustrate the impact and significance of priority scheduling in an ATM output queueing switch.

On the Influence of High Priority Customers on a Generalized Processor Sharing Queue

“…The result we get, is the pgf for a priority queueing system with 2 queues as can be found in [19]. This confirms our result.…”

“…As the mean queue length for class 1 is not influenced by the other queues and could also easily be calculated from results for single-class FCFS queueing, we will not discuss it here. Furthermore, we only analyze queue 2, as the system is work conserving, results for queue 3 follow easily from (19).…”

“…Priority queueing was, for instance, studied in [3,6,13,15,18,19]. Whereas, GPS was analyzed in [7,8,10,11,17,21].…”

Transform-Domain Analysis of Packet Delay in Network Nodes with QoS-Aware Scheduling

“…Clearly, no significant differentiation in the per-class delay distribution is expected under any of these disciplines. On the other hand, the most extreme way of service differentiation is AP (Absolute Priority) or 'HOL priority' (Head of Line), either preemptive or non-preemptive, see [45,47,24,9,48] as well as the contribution of Walraevens et al in this volume. Under AP, the next scheduled packet is the one that (1) belongs to the set of queued packets with highest priority and (2) has the longest waiting time of the packets in the set.…”

“…For QoS-aware scheduling mechanisms, the delay of P usually depends on how many of the present packets in the system are of type 1 and how many of type 2. In case of AP [47] however, it turns out that keeping track of the total system content u k alone is sufficient for the delay analysis, i.e. we require u k , leading again to (5)- (7).…”