Service Differentiation in OFDM-Based IEEE 802.16 Networks

Abstract

IEEE 802.16 network is widely viewed as a strong candidate solution for broadband wireless access systems. Various flexible mechanisms related to QoS provisioning have been specified for uplink traffic at the medium access control (MAC) layer in the standards. Among the mechanisms, bandwidth request scheme can be used to indicate and request bandwidth demands to the base station for different services. Due to the diverse QoS requirements of the applications, service differentiation (SD) is desirable for the bandwidth request scheme. In this paper, we propose several SD approaches. The approaches are based on the contention-based bandwidth request scheme and achieved by the means of assigning different channel access parameters and/or bandwidth allocation priorities to different services. Additionally, we propose effective analytical model to study the impacts of the SD approaches, which can be used for the configuration and optimization of the SD services. It is observed from simulations that the analytical model has high accuracy. Service can be efficiently differentiated with initial backoff window in terms of throughput and channel access delay. Moreover, the service differentiation can be improved if combined with the bandwidth allocation priority approach without adverse impacts on the overall system throughput.

Satellite-based fully distributed mesh hybrid networking technology DVB-S2/RCS-WiMAX for RRD areas

“…Unfortunately, such distributed multidimensional queuing models do not have a strict analytical solution in the realistic problem statement that takes into account the real conditions of a MAC operational environment. A few analytical models have been presented in literature to analyze the WiMAX-like MAC performance [8,[14][15][16][17]. However, it was possible to find the analytical results only under strong simplifying assumptions: one-dimensional infinite queues without priority, excluding errors, homogeneous traffic, static QoS control, short-delay medium (i.e., small round-trip-time), etc.…”

Performance analysis of the enhanced mesh MAC protocol of mobile WiMAX standard

“…RELATED WORK Nowadays, there are many performance analysis investigations of the IEEE 802.16 standard [9][10][11][12][13][14][15]. Several papers have studied the IEEE 802.16 performance metrics by simulation, theoretic analysis, or both.…”

“…Let we consider some of these researches. In [9][10][11][12] analytical approaches for performance analysis and protocol operating optimization based on Markovian process theory are presented. In [9,10] authors consider significant problem of resource allocation -they investigate meaning of the ratio between control and data slots and propose reservation period controller based on Markovian optimization model.…”

“…For the analysis authors have assumed that queues are saturated. In [12] authors investigate backoff mechanism for bandwidth request transmission. It is important to note, that recent analysis approaches have many simplifying assumptions, don't take into account some significant MAC-protocol parameters.…”

“…A lot of analytical solutions for WiMAX performance research based on Markovian process theory [9][10][11][12]. In [9][10] is presented study of reservation multiple access protocols.…”