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Communications Surveys & Tutorials, IEEE

Issue 2 • Date Second Quarter 2011

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  • Second Quarter 2011 IEEE Communications Surveys & Tutorials

    Page(s): 148 - 149
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    Freely Available from IEEE
  • A Survey of Distributed Search Techniques in Large Scale Distributed Systems

    Page(s): 150 - 167
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (801 KB) |  | HTML iconHTML  

    Peer-to-peer (P2P) technology has triggered a wide range of distributed applications beyond simple file-sharing. Distributed XML databases, distributed computing, server-less web publishing and networked resource/service sharing are only a few to name. Despite of the diversity in applications, these systems share a common problem regarding searching and discovery of information. This commonality stems from the transitory nodes population and volatile information content in the participating nodes. In such dynamic environment, users are not expected to have the exact information about the available objects in the system. Rather queries are based on partial information, which requires the search mechanism to be flexible. On the other hand, to scale with network size the search mechanism is required to be bandwidth efficient. In this survey, we identify the search requirements in large scale distributed systems and investigate the ability of the existing search techniques in satisfying these requirements. Representative search techniques from P2P content sharing, service discovery and P2P databases are considered in this work. View full abstract»

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  • A Survey of Communication Protocols for Automatic Meter Reading Applications

    Page(s): 168 - 182
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (5792 KB) |  | HTML iconHTML  

    Utility companies (electricity, gas, and water suppliers), governments, and researchers have been urging to deploy communication-based systems to read meters, known as automatic meter reading (AMR). An AMR system is envisaged to bring on benefits to customers, utilities, and governments. The advantages include reducing peak demand for energy, supporting the time-of-use concept for billing, enabling customers to make informed decisions, and reducing the cost of meter reading, to name a few. A key element in an AMR system is communications between meters and utility servers. Though several communication technologies have been proposed and implemented at a small scale, with the wide proliferation of wireless communication, it is the right time to critique the old proposals and explore new possibilities for the next generation AMR. We provide a comprehensive review of the AMR technologies proposed so far. Next, we present how future AMRs will benefit from third generation (3G) communication systems, the DLMS/COSEM (Data Language Messaging Specification/Companion Specification for Energy Metering) standard and Internet Protocol-based SIP (Session Initiation Protocol) signaling at the application level. The DLMS/COSEM standard provides a framework for meters to report application data (i.e. meter readings) to a utility server in a reliable manner. The SIP protocol is envisaged to be used as the signaling protocol between application entities running on meters and servers. The DLMS/COSEM standard and the SIP protocol are expected to provide an application level communication abstraction to achieve reliability and scalability. Finally, we identify the challenges at the application level that need to be tackled. The challenges include handling failure, gathering meter data under different time constraints (ranging from real-time to delay-tolerance), disseminating (i.e., unicasting, multicasting, broadcasting, and geocasting) control data to the meters, and achieving secure c ommunication. View full abstract»

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  • A Survey and Analysis of Media Keying Techniques in the Session Initiation Protocol (SIP)

    Page(s): 183 - 198
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (506 KB) |  | HTML iconHTML  

    Exchanging cryptographic keys to encrypt the media stream in the Session Initiation Protocol ({SIP}) has proven difficult. The challenge is to effectively exchange keys while preserving the features of the protocol (e.g., forking, re-targeting, request recursion, etc.), minimizing key exposure to unintended parties, eliminating voice clipping, maintaining end-to-end key privacy, interfacing with PSTN, etc. In this paper, we survey three key management protocols - SDES, ZRTP and DTLS-SRTP - that have been proposed for media keying, and evaluate them for use with SIP. To aid in the evaluation, we first extract (and justify) a core feature set from SIP. We then survey each key management protocol in detail and proceed to analyze the cores of the three protocols against this feature set to annotate their weaknesses and strengths. View full abstract»

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  • Securing BGP — A Literature Survey

    Page(s): 199 - 222
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1071 KB) |  | HTML iconHTML  

    The Border Gateway Protocol (BGP) is the Internet's inter-domain routing protocol. One of the major concerns related to BGP is its lack of effective security measures, and as a result the routing infrastructure of the Internet is vulnerable to various forms of attack. This paper examines the Internet's routing architecture and the design of BGP in particular, and surveys the work to date on securing BGP. To date no proposal has been seen as offering a combination of adequate security functions, suitable performance overheads and deployable support infrastructure. Some open questions on the next steps in the study of BGP security are posed. View full abstract»

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  • Energy Efficiency in the Future Internet: A Survey of Existing Approaches and Trends in Energy-Aware Fixed Network Infrastructures

    Page(s): 223 - 244
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1606 KB) |  | HTML iconHTML  

    The concept of energy-efficient networking has begun to spread in the past few years, gaining increasing popularity. Besides the widespread sensitivity to ecological issues, such interest also stems from economic needs, since both energy costs and electrical requirements of telcos' and Internet Service Providers' infrastructures around the world show a continuously growing trend. In this respect, a common opinion among networking researchers is that the sole introduction of low consumption silicon technologies may not be enough to effectively curb energy requirements. Thus, for disruptively boosting the network energy efficiency, these hardware enhancements must be integrated with ad-hoc mechanisms that explicitly manage energy saving, by exploiting network-specific features. This paper aims at providing a twofold contribution to green networking. At first, we explore current perspectives in power consumption for next generation networks. Secondly, we provide a detailed survey on emerging technologies, projects, and work-in-progress standards, which can be adopted in networks and related infrastructures in order to reduce their carbon footprint. The considered approaches range from energy saving techniques for networked hosts, to technologies and mechanisms for designing next-generation and energy-aware networks and networking equipment. View full abstract»

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  • Denial of Service Attacks in Wireless Networks: The Case of Jammers

    Page(s): 245 - 257
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (952 KB) |  | HTML iconHTML  

    The shared nature of the medium in wireless networks makes it easy for an adversary to launch a Wireless Denial of Service (WDoS) attack. Recent studies, demonstrate that such attacks can be very easily accomplished using off-the-shelf equipment. To give a simple example, a malicious node can continually transmit a radio signal in order to block any legitimate access to the medium and/or interfere with reception. This act is called jamming and the malicious nodes are referred to as jammers. Jamming techniques vary from simple ones based on the continual transmission of interference signals, to more sophisticated attacks that aim at exploiting vulnerabilities of the particular protocol used. In this survey, we present a detailed up-to-date discussion on the jamming attacks recorded in the literature. We also describe various techniques proposed for detecting the presence of jammers. Finally, we survey numerous mechanisms which attempt to protect the network from jamming attacks. We conclude with a summary and by suggesting future directions. View full abstract»

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  • Link Scheduling Algorithms for Wireless Mesh Networks

    Page(s): 258 - 273
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (536 KB) |  | HTML iconHTML  

    Wireless Mesh Networks (WMNs) have the potential of being a cost effective solution to provide connectivity and coverage in both urban and rural areas. Typically, a WMN is a backbone network that carries high data rate traffic and employs Time Division Multiple Access (TDMA) like access mechanisms. For a WMN to provide high throughput, the design of an efficient link scheduling algorithm is of paramount importance. Towards this end, we provide an overview of link scheduling algorithms in Spatial TDMA wireless mesh networks. These algorithms can be classified into three categories: those based only on a communication graph model of the network, those based on a communication graph model and Signal to Interference and Noise Ratio (SINR) threshold conditions at receivers and those based on an SINR graph model of the network. We first outline a framework for modeling STDMA networks. We review representative research works and provide the description of an algorithm from each of these classes. We describe the relative merits and demerits of each class of algorithms and compare their performance via simulations. We conclude with a discussion on practical implementation of these algorithms and open research problems. View full abstract»

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  • A Comparison Between the Centralized and Distributed Approaches for Spectrum Management

    Page(s): 274 - 290
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1796 KB) |  | HTML iconHTML  

    There is a growing demand for spectrum to accommodate future wireless services and applications. Given the rigidity of current allocations, several spectrum occupancy studies have indicated a low utilization over both space and time. Hence, to satisfy the demands of applications it can be inferred that dynamic spectrum usage is a required necessity. Centralized Dynamic Spectrum Allocation (DSA) and Distributed Dynamic Spectrum Selection (DSS) are two paradigms that aim to address this problem, whereby we use DSS (distributed) as an umbrella term for a range of terminologies for decentralized access, such as Opportunistic Spectrum Access and Dynamic Spectrum Access. This paper presents a survey on these methods, whereby we introduce, discuss, and classify several proposed architectures, techniques and solutions. Corresponding challenges from a technical point of view are also investigated, as are some of the remaining open issues. The final and perhaps most significant contribution of this work is to provide a baseline for systematically comparing the two approaches, revealing the pros and cons of DSA (centralized) and DSS (distributed) as methods of realizing spectrum sharing. View full abstract»

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  • Low-Memory Wavelet Transforms for Wireless Sensor Networks: A Tutorial

    Page(s): 291 - 307
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1016 KB) |  | HTML iconHTML  

    The computational and memory resources of wireless sensor nodes are typically very limited, as the employed low-energy microcontrollers provide only hardware support for 16 bit integer operations and have very limited random access memory (RAM). These limitations prevent the application of modern signal processing techniques to pre-process the collected sensor data for energy and bandwidth efficient transmission over sensor networks. This tutorial introduces communication and networking generalists without a background in wavelet signal processing to low-memory wavelet transform techniques. We first explain the one-dimensional wavelet transform (including the lifting scheme for in-place computation), the two-dimensional wavelet transform, as well as the evaluation of wavelet transforms with fixed-point arithmetic. Then, we explain the fractional wavelet filter technique which computes wavelet transforms with 16 bit integers and requires less than 1.5 kByte of RAM for a 256 × 256 gray scale image. We present case studies illustrating the use of these low-memory wavelet techniques in conjunction with image coding systems to achieve image compression competitive to the JPEG2000 standard on resource-constrained wireless sensor nodes. We make the C-code software for the techniques introduced in this tutorial freely available. View full abstract»

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Aims & Scope

IEEE Communications Surveys & Tutorials is an online journal published by the IEEE Communications Society for tutorials and surveys covering all aspects of the communications field. Telecommunications technology is progressing at a rapid pace, and the IEEE Communications Society is committed to providing researchers and other professionals the information and tools to stay abreast.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Ekram Hossain, Ph.D., P.Eng.
Professor
University of Manitoba