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Communications Magazine, IEEE

Issue 7 • Date July 2009

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Displaying Results 1 - 20 of 20
  • IEEE Communications Magazine - Front cover

    Publication Year: 2009 , Page(s): c1
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  • Table of contents

    Publication Year: 2009 , Page(s): 2 - 2, 4
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  • The path to becoming an IEEE Communications Society conference [The President's Page]

    Publication Year: 2009 , Page(s): 6 - 8
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  • Conference calendar

    Publication Year: 2009 , Page(s): 10 - 11
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  • New products

    Publication Year: 2009 , Page(s): 12
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  • Global communications newsletter

    Publication Year: 2009 , Page(s): 1 - 4
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  • Topics in network and service management [Series Editorial]

    Publication Year: 2009 , Page(s): 18 - 19
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  • Network virtualization: state of the art and research challenges

    Publication Year: 2009 , Page(s): 20 - 26
    Cited by:  Papers (127)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (126 KB) |  | HTML iconHTML  

    Recently network virtualization has been pushed forward by its proponents as a long-term solution to the gradual ossification problem faced by the existing Internet and proposed to be an integral part of the next-generation networking paradigm. By allowing multiple heterogeneous network architectures to cohabit on a shared physical substrate, network virtualization provides flexibility, promotes diversity, and promises security and increased manageability. However, many technical issues stand in the way of its successful realization. This article investigates the past and the state of the art in network virtualization along with the future challenges that must be addressed to realize a viable network virtualization environment. View full abstract»

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  • Future Internet = content + services + management

    Publication Year: 2009 , Page(s): 27 - 33
    Cited by:  Papers (15)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (863 KB) |  | HTML iconHTML  

    While the term future Internet has gained a lot of interest recently, there is little agreement on what this term means or what the future Internet looks like. By taking the viewpoint of an Internet user who is interested in using Internet services and not so much in the protocols that move data around, we first describe some possible future Internet services. In a second step we derive some network and service management requirements, and discuss some of them in more detail. View full abstract»

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  • With evolution for revolution: managing FEDERICA for future Internet research

    Publication Year: 2009 , Page(s): 34 - 39
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (446 KB) |  | HTML iconHTML  

    Over the last two decades the importance of data networking for human beings and systems has increased beyond any expectation in size, complexity, and impact on society. Today, technology offers the ubiquitous and constant possibility of being connected to the Internet at a wide range of speeds. Traditional management solutions have up to now followed an evolutionary path, although the scale of the Internet and emerging novel architectures such as peer-to-peer, ad hoc networks, as well as virtualization-capable network infrastructures require focused and possibly revolutionary changes in management approaches. This article elaborates on challenges posed by the renaissance of virtualization as experienced in the planning, development, and operation of the FEDERICA infrastructure. The European Community cofunded project FEDERICA, like other worldwide initiatives such as FIND/GENI in the United States, NWGN in Japan, and the FIRE program in Europe, is supporting the development of the future Internet. FEDERICA extends the virtualization capabilities of the current hardware and software to provide a flexible infrastructure to host disruptive testing by networking researchers. View full abstract»

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  • Managing interdomain traffic in Latin America: a new perspective based on LISP

    Publication Year: 2009 , Page(s): 40 - 48
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (236 KB) |  | HTML iconHTML  

    The characteristics of Latin American network infrastructures have global consequences, particularly in the area of interdomain traffic engineering. As an example, Latin America shows the largest de-aggregation factor of IP prefixes among all regional Internet registries, being proportionally the largest contributor to the growth and dynamics of the global BGP routing table. In this article we analyze the peculiarities of LA interdomain routing architecture, and provide up-to-date data about the combined effects of the multihoming and TE practices in the region. We observe that the Internet Research Task Force initiative on the separation of the address space into locators and identifiers can not only alleviate the growth and dynamics of the global routing table, but can also offer appealing TE opportunities for LA. We outline one of the solutions under discussion at the IRTF, the Locator/Identifier Separation Protocol, and examine its potential in terms of interdomain traffic management in the context of LA. The key advantage of LISP is its nondisruptive nature, but the existing proposals for its control plane have some problems that may hinder its possible deployment. In light of this, we introduce a promising control plane for LISP that can solve these issues, and at the same time has the potential to bridge the gap between intradomain and interdomain traffic management. View full abstract»

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  • Recent advances in amplify-and-forward two-hop relaying

    Publication Year: 2009 , Page(s): 50 - 56
    Cited by:  Papers (50)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (139 KB) |  | HTML iconHTML  

    In this article we review an important class of wireless cooperation protocols known as amplify-and-forward relaying. One or more low-complexity relay nodes assist the communication between sources and destinations without having to decode the signal. This makes AF relaying transparent to modulation and coding of the source/destination communication protocol. It is therefore a highly flexible technology that also qualifies for application in heterogeneous networks comprising many nodes of different complexity or even standards. Recently, two-way relaying was introduced, which is readily combined with AF relaying. It is a spectrally efficient protocol that allows for bidirectional communication between sources and destinations. In order to investigate the potential of wireless AF relaying, we introduce three distributed network scenarios that differ in the amount of cooperation between nodes. New challenges arise in those networks, and we discuss approaches to overcome them. For the most general case of a completely distributed system, we present coherent relaying solutions that offer a distributed spatial multiplexing gain even for single-antenna nodes. Based on real-world experiments, we validate the feasibility of all schemes in our laboratory. View full abstract»

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  • Tuning radio resource in an overlay cognitive radio network for TCP: Greed isn't good

    Publication Year: 2009 , Page(s): 57 - 63
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (423 KB) |  | HTML iconHTML  

    In this article we illustrate the performance of Transmission Control Protocol in an overlay cognitive radio network under dynamic spectrum access. We show that the performance of TCP in overlay CR networks that implement DSA to be quite different from its performance in conventional networks, which do not allow DSA. The key difference is that secondary users in an overlay CR network have to cope with a new type of loss called service interruption loss, due to the existence of primary users. We demonstrate on an NS2 simulation testbed the surprising result: Excessive radio resource usage leads to a decrease in aggregate TCP throughput. This behavior is in contrast to the behavior of TCP in conventional networks, where throughput increases monotonically with the available radio resource. View full abstract»

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  • Handover in multihop cellular networks

    Publication Year: 2009 , Page(s): 64 - 73
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (269 KB) |  | HTML iconHTML  

    This article introduces various handover scenarios in multihop cellular networks. In addition, this article presents handover schemes where relay stations are located either inside a cell or on the boundary between two adjacent cells and investigates the effects of the deployment position of relay stations to handover performance. The simulation results show that multihop cellular networks for both deployment scenarios can achieve 90 percent throughput increase over single-hop cellular networks. The results also show that the overall throughput of the multihop cellular networks with relay stations inside a cell is higher than for those with relay stations on the boundary between two adjacent cells, whereas the opposite is observed for the throughput of cell-boundary users. The intercell handover latency in multihop cellular networks is increased by 20 ~ 56 percent compared with that in single-hop cellular networks because of the increased number of handovers and signaling overhead. However, by deploying relay stations on the boundary between two adjacent cells, the service-interruption time caused by inter-cell handover is reduced by 80 percent compared with that of single-hop cellular networks. View full abstract»

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  • Securing wireless implantable devices for healthcare: Ideas and challenges

    Publication Year: 2009 , Page(s): 74 - 80
    Cited by:  Papers (9)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (704 KB) |  | HTML iconHTML  

    Implantable devices hold great potential for pervasive healthcare, enabling the identification, monitoring, and treatment of patients regardless of their location. To realize this goal, these devices must be able to communicate wirelessly with external devices. However, wireless communication presents many vulnerabilities: an attacker can eavesdrop on transmitted information, use implanted devices to track patients, or spoof an implanted device. An attacker even has the potential to cause direct physical harm to a patient, either by forcibly removing an implanted device from the patient or by maliciously sending commands that affect the operation of an implanted device. Addressing these security threats is crucial for implantable devices due to their permanent nature, but it is difficult because of the severe resource constraints facing such devices. This article details the threats that face wireless implantable devices, surveys the work addressing these threats, and identifies open issues for future research. View full abstract»

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  • Policy management for ENUM system enabling privacy and security

    Publication Year: 2009 , Page(s): 81 - 85
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    ENUM (telephone number mapping) is a key enabler in the convergence between IP-based networks and the traditional PSTNs that may result in additional complexity in commercial relationships and regulation of the telecommunications sector. In particular, the current ENUM may significantly increase the risk of unscrupulous use of the information managed (e.g., public user identifiers and user/service reachability). The aim of this article is to describe a new functional reference model for ENUM, and provide some new requirements that enable user privacy and security. View full abstract»

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  • An overview of downlink radio resource management for UTRAN long-term evolution

    Publication Year: 2009 , Page(s): 86 - 93
    Cited by:  Papers (30)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (231 KB) |  | HTML iconHTML  

    Radio resource management algorithms ranging from bearer admission control to semi-persistent and dynamic packet scheduling, fast link adaptation, and transmission control of multi-antenna transmission modes are addressed in this article for UTRAN long-term evolution. First, a high-level system overview of LTE is given, with special emphasis on the important components related to RRM. The quality of service parameter framework is outlined, as one of the main objectives for the families of RRM algorithms is to maximize system capacity while serving all users according to their minimum QoS constraints. It is demonstrated how the collocation of the RRM algorithms at the base station with easy access to air interface measurements offers opportunities for efficient cross-functional optimization between layers 1, 2, and 3. Examples of performance results for different traffic mixes and antenna transmission schemes are also presented, and the article is concluded with recommendations on how to operate the various RRM options under different load and traffic conditions. View full abstract»

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  • A new class of floating-point data formats with applications to 16-bit digital-signal processing systems

    Publication Year: 2009 , Page(s): 94 - 101
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (156 KB) |  | HTML iconHTML  

    Sixteen-bit, programmable, digital-signal processors suffer from inadequate dynamic range and noise performance due in part to the use of standard data formats with few bits available for numeric precision. A solution to this problem is developed that involves the use of irregular data formats. A new class of irregular floating-point formats is developed. A specific format is derived from this class that provides greater dynamic range and improved noise performance for 16-bit DSP applications. An experiment with one of the new formats is conducted and analyzed, and improved performance is verified. The importance of our work and its potential applications are discussed. View full abstract»

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  • Understanding interference and carrier sensing in wireless mesh networks

    Publication Year: 2009 , Page(s): 102 - 109
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (901 KB) |  | HTML iconHTML  

    Wireless mesh networks aim to provide high-speed Internet service without costly network infrastructure deployment and maintenance. The main obstacle in achieving high-capacity wireless mesh networks is interference between the mesh links. In this article, we analyze the carrier sensing and interference relations between two wireless links and measure the impact of these relations on link capacity on an indoor 802.11a mesh network testbed. We show that asymmetric carrier sensing and/or interference relations commonly exist in wireless mesh networks, and we study their impact on the link capacity and fair-channel access. In addition, we investigate the effect of traffic rate on link capacity in the presence of interference. View full abstract»

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  • Advertisers' index

    Publication Year: 2009 , Page(s): 112
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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