Abstract—Radio Resource Management (RRM) techniques used in the Worldwide Interoperability for Microwave Access (WiMAX) can provide for many of the services and features promised by 4G wireless networks, such as supporting multimedia services with high data rates, and wide coverage area, as well as all-IP with security and Quality of Service (QoS) support. The IEEE 802.16 standard, associated with the WiMAX, leaves the details of RRM components open for the vendors to explore. In this paper we propose a novel scheme for the QoS support in WiMAX including packet scheduling and bandwidth allocation strategies. The proposed solution efficiently enhances performance and utilizes resources, while being fair, practical and in compliance with the IEEE 802.16 standard specifications. Our solution provides QoS support to all traffic classes defined by the standard, and it dynamically changes the bandwidth allocation based on the traffic characteristics and service demands. Simulation results show that the proposed solution can deliver QoS support and be fair to all classes of service in a WiMAX network. Keywords- Packet Scheduling; QoS support; Inter-Class and Intra-Class QoS support I. INTRODUCTION WiMAX is designed to provide high speed wireless access in metropolitan area networks. RRM techniques and QoS support are among the most important features of this technology. WiMAX is associated with the IEEE 802.16 standard, which defines five classes of traffic flows representing different types of services in the following order: Unsolicited Grant Service (UGS), Extended Real Time Polling Service (ertPS), Real Time Polling Service (rtPS), Non-Real Time Polling Service (nrtPS), and Best Effort Service (BE). The standard defines a connection-oriented MAC protocol with a mechanism for the QoS support. However, RRM techniques such as Packet Scheduling (PS) and Bandwidth Allocation (BA) schemes are left open for development by the vendors. In this study, we propose a new scheme for the QoS support that includes PS and BA called 2Tier-QoS Framework (2T- QoSFW). The proposed solution supports all types of service flows, and makes bandwidth allocation technique that is dynamic and fair, and utilizes the resources in an efficient way. The motivation for this study is to develop RRM schemes that consider fairness and utilization, and to establish parameters to quantify their values. The proposed solution separates the traffic and provides QoS support in two levels: Inter-Class and Intra-Class. The components of the solution (PS and BA) are implemented in two main building blocks: Tier-1 and Tier-2, and they work based on two fundamental ideas: (i) Dynamic bandwidth allocation based on traffic arrival rate, (ii) Intra-class versus inter-class QoS support. The QoS support is incorporated into the solution using fairness and utilization. In WiMAX applications, fairness is related to bandwidth allocation among different service classes. There are several definitions and methods for evaluating fairness such as Jain’s fairness, Gini coefficient, Max-Min fairness [6]. Utilization in WiMAX networks depends on application demands, user density, and available network resources. In this paper we define fairness and utilization as the ratios of allocated bandwidth (bw alloc ) by the requested bandwidth (bw req ), and throughput achieved (Th) by bw alloc respectively. The rest of this paper is organized in the following order. Section II reviews some of the works done by the research community in PS and BA for WiMAX. Section III describes our proposed solution including system architecture and modeling features. Section IV includes preliminary simulation results. Finally, we make a conclusion and list future plans for this study in Section V. II. LITERATURE REVIEW RRM for IEEE 802.16 and WiMAX has been studied by many groups in the wireless research community. Several schemes are proposed for PS and BA. RRM schemes are categorized based on centralized/decentralized, Real-Time (RT) versus Non-Real-Time (NRT), Uplink (UL) and Downlink (DL) or basic versus complex schemes. In the basic schemes, often a simple traditional queuing discipline is considered for PS in all classes [1]. Such systems use one or two simple queue disciplines to separate the traffic. Giving different weights to various classes to highlight their priorities is also used as a common strategy. Proposals based on complex schemes for PS and BA combine several queuing disciplines with some parameters related to traffic and medium characteristics. They often develop schemes in more than one stage. Complex Hierarchical schemes are proposed in [2, 3]. In hierarchical schemes, the PS and BA are designed in multiple levels. Often the traffic from different service classes is separated in the first level, and then scheduled within each class in the second level. Different levels of RRM could all be performed in the BS or the tasks could be divided between BS and SSs. In [5], the authors propose an Ad-hoc scheme for scheduling, where a separate queuing discipline is used for each service flow. From a different perspective, the RRM could be classified based on QoS support strategies. Most of the proposed Amir Esmailpour Department of Electrical and Computer Engineering University of Toronto Toronto, Canada Amir.Esmailpour@utoronto.ca Nidal Nasser Department of Computing and Information Science University of Guelph Guelph, Canada N1G 2W1 nnasser@uoguelph.ca A Novel Scheme for Packet Scheduling and Bandwidth Allocation in WiMAX Networks 978-1-61284-231-8/11/$26.00 ©2011 IEEE This full text paper was peer reviewed at the direction of IEEE Communications Society subject matter experts for publication in the IEEE ICC 2011 proceedings