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Communications Magazine, IEEE

Issue 6 • Date June 2002

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Displaying Results 1 - 16 of 16
  • Report from the vice president - membership services

    Publication Year: 2002 , Page(s): 6 - 8
    Cited by:  Papers (1)
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    Freely Available from IEEE
  • Topics in broadband access [guest editorial]

    Publication Year: 2002 , Page(s): 88
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    Freely Available from IEEE
  • IEEE standard 802.16: a technical overview of the WirelessMAN/sup TM/ air interface for broadband wireless access

    Publication Year: 2002 , Page(s): 98 - 107
    Cited by:  Papers (256)  |  Patents (58)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (93 KB) |  | HTML iconHTML  

    The broadband wireless access industry, which provides high-rate network connections to stationary sites, has matured to the point at which it now has a standard for second-generation wireless metropolitan area networks. The IEEE standard 802.16, with its WirelessMAN/sup TM/ air interface, sets the stage for widespread and effective deployments worldwide. This article overviews the technical medium access control and physical layer features of this new standard. View full abstract»

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  • A comparison of active queue management algorithms using the OPNET Modeler

    Publication Year: 2002 , Page(s): 158 - 167
    Cited by:  Papers (21)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (128 KB) |  | HTML iconHTML  

    A number of active queue management algorithms for TCP/IP networks such as random early detection (RED), stabilized RED (SRED), BLUE, and dynamic RED (DRED) have been proposed in the past few years. This article presents a comparative study of these algorithms using simulations. The evaluation is done using the OPNET Modeler, which provides a convenient and easy-to-use platform for simulating large-scale networks. The performance metrics used in the study are queue size, packet drop probability, and packet loss rate. The study shows that, among the four algorithms, SIZED and DRED are more effective at stabilizing the queue size and controlling the packet loss rate while maintaining high link utilization. The benefits of stabilized queues in a network are high resource utilization, bounded delays, more certain buffer provisioning, and,traffic-load-independent network performance in terms of traffic intensity and number of TCP connections. View full abstract»

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  • Bluetooth in wireless communication

    Publication Year: 2002 , Page(s): 90 - 96
    Cited by:  Papers (26)  |  Patents (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1401 KB) |  | HTML iconHTML  

    Bluetooth is a method for data communication that uses short-range radio links to replace cables between computers and their connected units. Industry-wide Bluetooth promises very substantial benefits for wireless network operators, end workers, and content developers of exciting new applications. This article delves into the implementation and architecture of Bluetooth. It also describes the functional overview and applications of Bluetooth, and deals with the development of a model for recording, printing, monitoring, and controlling of eight process variables at the same time, using a distributed control system. We explain industrial automation via Bluetooth using IISS. Industrial automation is one of the major applications of Bluetooth technology. Industrial automation, in terms of controlling or monitoring a factory, office, or industrial process, means to install machines that can do the work instead of human workers. Industrial plants consists of many devices interconnected in different ways ranging from simple data collection units (I/O) to more intelligent devices such as sensors, one-loop controllers, or programmable controllers, and a supervisory system used as a human-machine interface (HMI) for data logging and supervisory control. An IISS is a controlling device that monitors the devices in a company. It basically communicates via the interface card in the PC; the hardware is connected parallel across the device, and it is interfaced with the PC via a transceiver. The device can be accessed both manually via the switches and remotely via the PC. A simulation of connecting a PC with the machines in a company was executed. Also, we wrote a software program using C language; we will show how the remote monitoring takes place between the control room and the PC. These details in the article establish the growing need for Bluetooth technology View full abstract»

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  • Communication system performance: achieving the ultimate information-theoretic limits?

    Publication Year: 2002 , Page(s): 124 - 129
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1011 KB) |  | HTML iconHTML  

    The role of information theory in communications is considered, the former giving the ultimate limits and sometimes showing how to approach them. A survey of the development of telephone channel modems, where the capacity is practically achieved, is presented. As a contrast, an account of multi-antenna systems is included, where a long journey to achieve capacity has just begun. A very important characteristic of multi-antenna systems is stressed: the capacity increases almost linearly with respect to the transmitted power as the number of antennas increases, keeping the corresponding bandwidth constant View full abstract»

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  • A survey of QoS multicasting issues

    Publication Year: 2002 , Page(s): 82 - 87
    Cited by:  Papers (20)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (992 KB) |  | HTML iconHTML  

    The proliferation of QoS-aware group applications over the Internet has accelerated the need for scalable and efficient multicast support. We present a multicast "life cycle" model that identifies the various issues involved in a typical multicast session. During the life cycle of a multicast session, three important events can occur: group dynamics, network dynamics, and traffic dynamics. The first two aspects are concerned with maintaining a good-quality (e.g., cost) multicast tree taking into account member join/leave and changes in the network topology due to link/node failures/additions, respectively. The third aspect is concerned with flow, congestion, and error control. We examine various issues and solutions for managing group dynamics and failure handling in QoS multicasting, and outline several future research directions View full abstract»

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  • HiperLAN2: broadband wireless communications at 5 GHz

    Publication Year: 2002 , Page(s): 130 - 136
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1109 KB) |  | HTML iconHTML  

    Solutions for high data rates and local coverage have been developed over a couple of years in the area of wireless local area networking. The quality of service, security, mobility, and high throughput are key components that drive the standards for broadband wireless multimedia communications presently being developed in Europe as well as in the United States and Japan for the 5 GHz band. These technologies are well suited to complement third-generation cellular networks. HiperLAN type 2 (HiperLAN2) is one of these systems, which is being specified by the ETSI project BRAN. The core parts of the specification were finalized at the end of 1999. Almost total harmonization has been achieved between the standardization bodies in Europe and Japan (ETSI and ARIB, respectively). HiperLAN2 will provide data rates up to 54 Mb/s, and is intended for local communications in indoor and outdoor environments. An overview of the HiperLAN2 standard is presented together with exemplary link and system performance results View full abstract»

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  • Adaptive modulation and MIMO coding for broadband wireless data networks

    Publication Year: 2002 , Page(s): 108 - 115
    Cited by:  Papers (163)  |  Patents (42)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1421 KB) |  | HTML iconHTML  

    Link adaptation techniques, where the modulation, coding rate, and/or other signal transmission parameters are dynamically adapted to the changing channel conditions, have emerged as powerful tools for increasing the data rate and spectral efficiency of wireless data-centric networks. While there has been significant progress on understanding the theoretical aspects of time adaptation in LA protocols, new challenges surface when dynamic transmission techniques are employed in broadband wireless networks with multiple signaling dimensions. Those additional dimensions are mainly frequency, especially in multicarrier systems, and space in multiple-antenna systems, particularly multiarray multiple-input multiple-output communication systems. We give an overview of the challenges and promises of link adaptation in future broadband wireless networks. We suggest guidelines to help in the design of robust, complexity/cost-effective algorithms for these future wireless networks View full abstract»

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  • Restorable dynamic quality of service routing

    Publication Year: 2002 , Page(s): 72 - 81
    Cited by:  Papers (23)  |  Patents (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1783 KB) |  | HTML iconHTML  

    The focus of quality-of-service routing has been on the routing of a single path satisfying specified QoS constraints. Upon failure of a node or link on the path, a new path satisfying the constraints has to be established. However, resources needed to satisfy the QoS requirements are not guaranteed to be available at the rerouting instant, so QoS is not guaranteed upon failure. Restorable QoS routing, where active and backup paths must be simultaneously set up, has been previously studied. This is mostly motivated by the incorporation of mechanisms to establish QoS guaranteed paths with failure protection in multiprotocol label switching networks. This article describes some previously developed algorithms for dynamic routing of restorable QoS guaranteed paths View full abstract»

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  • Self-organizing packet radio ad hoc networks with overlay (SOPRANO)

    Publication Year: 2002 , Page(s): 149 - 157
    Cited by:  Papers (49)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1609 KB) |  | HTML iconHTML  

    The SOPRANO project involves a novel adaptive and scalable wireless network architecture utilizing a mixture of cellular and multihop packet radio system topologies with the potential to support a variety of applications including high-data rate Internet and multimedia traffic at a reasonable degree of implementation complexity. This article discusses the potential benefits of this structure and addresses several relevant issues necessary to support such a network. More specifically, it focuses on connection establishment and self-organization, investigates the formulation of an optimum transmission strategy, and examines some of the techniques by which we can augment the capacity or enhance the system performance in this multihop network. We also present capacity bounds that illustrate how these techniques help in trading off conserved power for a multifold capacity advantage View full abstract»

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  • A localized adaptive proportioning approach to QoS routing

    Publication Year: 2002 , Page(s): 66 - 71
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1216 KB) |  | HTML iconHTML  

    In QoS routing, paths for flows are selected based on knowledge of resource availability at network nodes and the QoS requirements of flows. Several QoS routing schemes have been proposed that differ in the way they gather information about the network state and select paths based on this information. We broadly categorize these schemes into best path routing and proportional routing. The best path routing schemes gather global network state information and always select the best path for an incoming I-low,based on this global view. It has been shown that best path routing schemes require frequent exchange of network state, imposing both communication overhead on the network and processing overheads on the core routers. On the other hand, proportional routing schemes proportion incoming flows among a set of candidate paths. We have shown that it is possible to compute near-optimal proportions using only locally collected information. Furthermore, a few good candidate paths can be selected using infrequently exchanged global information and thus with minimal communication overhead. We describe these schemes in detail and demonstrate that proportional routing schemes can achieve higher throughput with lower overhead than best path routing schemes View full abstract»

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  • Realizing the transition to IPv6

    Publication Year: 2002 , Page(s): 138 - 147
    Cited by:  Papers (26)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2193 KB) |  | HTML iconHTML  

    While the details of the next-generation IPv6 protocol are now reaching maturity, the next hurdle in realizing the promises of IPv6 is the need for deployment on a wider scale. Previously, the migration from IPv4 to IPv6 has been considered nontrivial, a factor generally attributed to thwarting its success. However, with the advent of a number of new transitioning techniques the evolution to IPv6 is now becoming increasingly feasible. These transitioning techniques offer tunneling and translation solutions that enable the gradual introduction of IPv6 support into an existing IPv4 infrastructure. Nevertheless, it is not yet clear what form this evolution is likely to take, which phases are likely to exist, and how the transition process will proceed. This article examines existing IETF IPv6 transitioning mechanisms and discusses the key issues involved in IPv6 deployment. We examine those aspects that potentially affect the choice of transition mechanisms and look at what factors are likely to mould the evolutionary path View full abstract»

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  • QoS routing granularity in MPLS networks

    Publication Year: 2002 , Page(s): 58 - 65
    Cited by:  Papers (14)  |  Patents (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1960 KB) |  | HTML iconHTML  

    This study investigates how constraint-based routing decision granularity significantly affects the scalability and blocking performance of QoS routing in an MPLS network. Coarse granularity, such as per-destination, has lower storage and computational overheads but is only suitable for best effort traffic. On the other hand, fine granularity, such as per-flow, provides lower blocking probability for bandwidth requests, but requires a huge number of states and high computational cost. To achieve cost-effective scalability, this study proposes using hybrid granularity schemes. The overflowed cache of the per-pair/flow scheme adds a per-pair cache and a per-flow cache as the routing cache, and performs well in blocking probability. The per-pair/class scheme groups the flows into several paths using routing marks, thus allowing packets to be label-forwarded with a bounded cache View full abstract»

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  • Multicast: wired to wireless

    Publication Year: 2002 , Page(s): 116 - 123
    Cited by:  Papers (24)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1650 KB) |  | HTML iconHTML  

    There has been an increasing demand for applications like multiplayer online gaming, where players residing in different parts of the world participate in the same gaming session through the Internet. Multicasting could prove to be an efficient way of providing necessary services for these applications. Furthermore, with the increasing popularity of handheld devices and mobile equipment, it is imperative to determine the best way to provide these services in a wireless environment. Due to very diverse requirements, it is necessary to investigate and discern the applicability of existing multicast protocols and qualify which is more suitable for which types of applications. This article provides a detailed description and comparison of IP-based wired and wireless multicast protocols. We hope that the discussion presented will be helpful to application developers in selecting an appropriate multicast protocol for their specific needs View full abstract»

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  • QoS routing for anycast communications: motivation and an architecture for DiffServ networks

    Publication Year: 2002 , Page(s): 48 - 56
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1577 KB) |  | HTML iconHTML  

    Much research in QoS routing has focused on the unicast communication paradigm. However, another communication paradigm - anycasting - has grown in importance. In the anycast paradigm, one endpoint is specified and the other is selected from a set of "equivalent" endpoints. An anycast service in a QoS-based network requires selection of both an endpoint and a path that satisfies a QoS constraint. This article provides background material on anycasting in both best-effort networks and QoS-based networks. We then focus on the differentiated services QoS model, and present the design of a QoS-based anycasting architecture consistent with that model. Via simulations, we explore the design options implied by the architecture, including signaling protocols, server selection/sorting algorithms, and resource reservation granularity. We conclude by highlighting open problems in the emerging area of QoS-based anycasting View full abstract»

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Aims & Scope

IEEE Communications Magazine covers all areas of communications such as lightwave telecommunications, high-speed data communications, personal communications systems (PCS), ISDN, and more.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Osman Gebizlioglu
Huawei Technologies