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  • 1.
    Degermark, Mikael
    et al.
    Luleå tekniska universitet.
    Engan, Mathias
    Luleå tekniska universitet.
    Nordgren, Björn
    Luleå tekniska universitet.
    Pink, Stephen
    Luleå University of Technology.
    Low-loss TCP/IP header compression for wireless networks1997In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 3, no 5, p. 375-387Article in journal (Refereed)
    Abstract [en]

    Wireless is becoming a popular way to connect mobile computers to the Internet and other networks. The bandwidth of wireless links will probably always be limited due to properties of the physical medium and regulatory limits on the use of frequencies for radio communication. Therefore, it is necessary for network protocols to utilize the available bandwidth efficiently. Headers of IP packets are growing and the bandwidth required for transmitting headers is increasing. With the coming of IPv6 the address size increases from 4 to 16 bytes and the basic IP header increases from 20 to 40 bytes. Moreover, most mobility schemes tunnel packets addressed to mobile hosts by adding an extra IP header or extra routing information, typically increasing the size of TCP/IPv4 headers to 60 bytes and TCP/IPv6 headers to 100 bytes. In this paper, we provide new header compression schemes for UDP/IP and TCP/IP protocols. We show how to reduce the size of UDP/IP headers by an order of magnitude, down to four to five bytes. Our method works over simplex links, lossy links, multi-access links, and supports multicast communication. We also show how to generalize the most commonly used method for header compression for TCP/IPv4, developed by Jacobson, to IPv6 and multiple IP headers. The resulting scheme unfortunately reduces TCP throughput over lossy links due to unfavorable interaction with TCP's congestion control mechanisms. However, by adding two simple mechanisms the potential gain from header compression can be realized over lossy wireless networks as well as point-to-point modem links.

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  • 2.
    Khan, Zaheer
    et al.
    Centre for Wireless Communications, University of Oulu.
    Lehtomäki, Janne
    Centre for Wireless Communications, University of Oulu.
    Vasilakos, Athanasios V.
    Centre for Wireless Communications, University of Oulu.
    MacKenzie, Allen B.
    Centre for Wireless Communications, University of Oulu.
    Juntti, Markku
    Centre for Wireless Communications, University of Oulu.
    Adaptive wireless communications under competition and jamming in energy constrained networks2018In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 24, no 1, p. 151-171Article in journal (Refereed)
    Abstract [en]

    We propose a framed slotted Aloha-based adaptive method for robust communication between autonomous wireless nodes competing to access a channel under unknown network conditions such as adversarial disruptions. With energy as a scarce resource, we show that in order to disrupt communications, our method forces the reactive adversary to incur higher energy cost relative to a legitimate node. Consequently, the adversary depletes its energy resources and stops attacking the network. Using the proposed method, a transmitter node changes the number of selected time slots and the access probability in each selected time slot based on the number of unsuccessful transmissions of a data packet. On the receiver side, a receiver node changes the probability of listening in a time slot based on the number of unsuccessful communication attempts of a packet. We compare the proposed method with two other framed slotted Aloha-based methods in terms of average energy consumption and average time required to communicate a packet. For performance evaluation, we consider scenarios in which: (1) Multiple nodes compete to access a channel. (2) Nodes compete in the presence of adversarial attacks. (3) Nodes compete in the presence of channel errors and capture effect.

  • 3.
    Khan, Zaheer
    et al.
    Centre for Wireless Communications, University of Oulu.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Barua, Bidushi
    Centre for Wireless Communications, University of Oulu.
    Shahabuddin, Shahriar
    Centre for Wireless Communications, University of Oulu.
    Ahmadi, Hamed
    CTVR, Trinity College Dublin.
    Cooperative content delivery exploiting multiple wireless interfaces: methods, new technological developments, open research issues and a case study2016In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 22, no 6, p. 1961-1983Article in journal (Refereed)
    Abstract [en]

    In this tutorial paper, we discuss and compare cooperative content delivery (CCD) techniques that exploit multiple wireless interfaces available on mobile devices to efficiently satisfy the already massive and rapidly growing user demand for content. The discussed CCD techniques include simultaneous use of wireless interfaces, opportunistic use of wireless interfaces, and aggregate use of wireless interfaces. We provide a taxonomy of different ways in which multiple wireless interfaces are exploited for CCD, and also discuss the real measurement studies that evaluate the content delivery performance of different wireless interfaces in terms of energy consumption and throughput. We describe several challenges related to the design of CCD methods using multiple interfaces, and also explain how new technological developments can help in accelerating the performance of such CCD methods. The new technological developments discussed in this paper include wireless interface aggregation, network caching, and the use of crowdsourcing. We provide a case study for selection of devices in a group for CCD using multiple interfaces. We consider this case study based on the observation that in general different CCD users can have different link qualities in terms of transmit/receive performance, and selection of users with good link qualities for CCD can accelerate the content delivery performance of wireless networks. Finally, we discuss some open research issues relating to CCD using multiple interfaces.

  • 4.
    Li, Changle
    et al.
    State Key Laboratory of Integrated Services Networks, Xidian University.
    Zhang, Beibei
    State Key Laboratory of Integrated Services Networks, Xidian University.
    Yuan, Xiaoming
    State Key Laboratory of Integrated Services Networks, Xidian University.
    Ullah, Sana
    Department of Computer and Software Technology, University of Swat.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    MC-MAC: a multi-channel based MAC scheme for interference mitigation in WBANs2018In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 24, no 3, p. 719-733Article in journal (Refereed)
    Abstract [en]

    Wireless body area networks (WBANs) support the inter-operability of biomedical sensors and medical institutions with convenience and high-efficiency, which makes it an appropriate solution for the pervasive healthcare. Typically, WBANs comprise in-body or around-body sensor nodes for collecting data of physiological feature. Therefore, the efficient medium access control (MAC) protocol is a crucial paramount to coordinate these devices and forward data to the medical center in an efficient and reliable way. However, the extensive use of wireless channel and coexistence of WBANs may result in inevitable interference which will cause performance degradation. Besides, contention-based access in single channel in WBANs is less efficient for dense medical traffic on account of large packet delay, energy consumption and low priority starvation. To address these issues above, we propose a multi-channel MAC (MC-MAC) scheme to obtain better network performance. Considering the characteristic and emergency degree of medical traffic, we introduce a novel channel mapping and selection mechanism, cooperating with conflict avoidance strategy, to organize nodes to access available channels without collisions. In addition, we have evaluated the performance of MC-MAC and the standard IEEE 802.15.6 via simulation and hardware test. The test is conducted by hardware platform based on prototype system of WBANs. Both of the analysis and simulation results show that MC-MAC outperforms the IEEE 802.15.6 in terms of packet delay, throughput, packet error rate and frame error rate

  • 5.
    Li, Xiaomin
    et al.
    School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou.
    Li, Di
    School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou.
    Wan, Jiafu
    School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Lai, Chinfeng
    Department of Computer Science and Information Engineering, National Chung Cheng University, Jiayi.
    Wang, Shiyong
    School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou.
    A review of industrial wireless networks in the context of Industry 4.02017In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 23, no 1, p. 23-41Article in journal (Refereed)
    Abstract [en]

    There have been many recent advances in wireless communication technologies, particularly in the area of wireless sensor networks, which have undergone rapid development and been successfully applied in the consumer electronics market. Therefore, wireless networks (WNs) have been attracting more attention from academic communities and other domains. From an industrial perspective, WNs present many advantages including flexibility, low cost, easy deployment and so on. Therefore, WNs can play a vital role in the Industry 4.0 framework, and can be used for smart factories and intelligent manufacturing systems. In this paper, we present an overview of industrial WNs (IWNs), discuss IWN features and related techniques, and then provide a new architecture based on quality of service and quality of data for IWNs. We also propose some applications for IWNs and IWN standards. Then, we will use a case from our previous achievements to explain how to design an IWN under Industry 4.0. Finally, we highlight some of the design challenges and open issues that still need to be addressed to make IWNs truly ubiquitous for a wide range of applications. 

  • 6.
    Lin, Di
    et al.
    School of Information and Software Engineering, University of Electronic Science and Technology of China, Chengdu.
    Labeau, Fabrice
    Department of Electrical and Computer Engineering, McGill University, Montreal.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    QoE-based optimal resource allocation in wireless healthcare networks: opportunities and challenges2015In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 21, no 8, p. 2483-2500Article in journal (Refereed)
    Abstract [en]

    Ubiquitous health monitoring is a mobile health service with the aim of monitoring patients’ conditions anytime and anywhere by collecting and transferring biosignal data from patients to health-service providers (e.g., healthcare centers). As a critical issue in ubiquitous health monitoring, wireless resource allocation can influence the performance of health monitoring, and the majority of work in wireless resource allocation for health monitoring has focused on quality-of-service oriented allocation schemes with primary challenges at the physical and MAC layers. Recently, quality-of-experience (QoE) oriented resource allocation schemes in wireless health monitoring have attracted attentions as a promising design to a better service of healthcare monitoring. In this paper, we overview the metrics of assessing the quality of medical images, and discuss the performance of these metrics in QoE-oriented resource allocation for health monitoring. We start with addressing the state-of-the-art QoE metrics by providing a taxonomy of the different metrics employed in assessing medical images. We then present the design of resource allocation schemes for health monitoring. After that, we present a case study to compare the performance of different classes of metrics in designing resource allocation schemes. We end the paper with a few open issues in the design of novel QoE metrics for resource allocation in health monitoring.

  • 7.
    Moetesum, Momina
    et al.
    Department of Computer Science, Bahria University, Islamabad.
    Hadi, Fazle
    Department of Computer Science, Bahria University, Islamabad.
    Imran, Muhammad Al
    College of Computer and Information Sciences, Almuzahmiyah, King Saud University.
    Minhas, Abid Ali
    Department of Computer Science, Bahria University, Islamabad.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    An adaptive and efficient buffer management scheme for resource-constrained delay tolerant networks2016In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 22, no 7, p. 2189-2201Article in journal (Refereed)
    Abstract [en]

    Provisioning buffer management mechanism is especially crucial in resource-constrained delay tolerant networks (DTNs) as maximum data delivery ratio with minimum overhead is expected in highly congested environments. However, most DTN protocols do not consider resource limitations (e.g., buffer, bandwidth) and hence, results in performance degradation. To strangle and mitigate the impact of frequent buffer overflows, this paper presents an adaptive and efficient buffer management scheme called size-aware drop (SAD) that strives to improve buffer utilization and avoid unnecessary message drops. To improve data delivery ratio, SAD exactly determines the requirement based on differential of newly arrived message(s) and available space. To vacate inevitable space from a congested buffer, SAD strives to avoid redundant message drops and deliberate to pick and discard most appropriate message(s) to minimize overhead. The performance of SAD is validated through extensive simulations in realistic environments (i.e., resource-constrained and congested) with different mobility models (i.e., Random Waypoint and disaster). Simulation results demonstrate the performance supremacy of SAD in terms of delivery probability and overhead ratio besides other metrics when compared to contemporary schemes based on Epidemic (DOA and DLA) and PRoPHET (SHLI and MOFO).

  • 8.
    Niu, Hao
    et al.
    Institute of Industrial Science, University of Tokyo.
    Zhu, Nanhao
    CETC Group, GCI Science and Technology Co.
    Sun, Li
    Department of Information and Communications Engineering, Xi’an Jiaotong University, Xi’an.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Sezaki, Kaoru
    Institute of Industrial Science, University of Tokyo.
    Security-embedded opportunistic user cooperation with full diversity2016In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 22, no 5, p. 1513-1522Article in journal (Refereed)
    Abstract [en]

    As a promising technique for wireless networks, cooperative communications is coming to maturity in both theory and practice. The main merit of the cooperation technique is its capability in providing additional transmission links to harvest the spatial diversity gain at the physical layer. However, due to the broadcast nature of wireless medium, the diversity gain can be also freely achieved at the potential eavesdropper if the cooperation is performed blindly. To solve this problem, we propose a security-embedded opportunistic user cooperation scheme (OUCS) in this paper. The OUCS first defines a concept called secrecy-providing capability (SPC) for both the source and the cooperative relays. By comparing the values of SPC of these nodes, the OUCS jointly decides whether to cooperate and with whom to cooperate from the perspective of physical layer security. The secrecy outage performance of the OUCS is then derived. From the results we prove that full diversity can be achieved (i.e., the diversity order is N + 1 for N cooperative relays), which outperforms existing alternatives. Finally, numerical results are provided to validate the theoretical analysis.

  • 9.
    Poirot, Valentin
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Ericson, Mårten
    Ericsson Research, 977 53, Luleå, Sweden.
    Nordberg, Mats
    Ericsson Research, 977 53, Luleå, Sweden.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Energy efficient multi-connectivity algorithms for ultra-dense 5G networks2020In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 26, no 3, p. 2207-2222Article in journal (Refereed)
    Abstract [en]

    Two radio air interfaces, Evolved-LTE and New Radio, coexist in new 5G systems. New Radio operates in the millimeter band and provides a better bandwidth, but the higher frequencies also imply worse radio conditions. Multi-connectivity, a feature of 5G that allows users to connect to more than one base station simultaneously, can offer the advantages of both interfaces. In this paper, we investigate how multi-connectivity can improve user reliability and the system’s energy efficiency. Five algorithms for secondary cell association are presented and evaluated. We show a decrease in the radio link failure rate of up to 50% at high speeds and improvements of the energy efficiency of up to 20% at low speeds.

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    fulltext
  • 10.
    Rasheed, Muhammad Babar
    et al.
    COMSATS Institute of Information Technology, Islamabad.
    Javaid, Nadeem
    COMSATS Institute of Information Technology, Islamabad.
    Imran, Muhammad Al
    College of Computer and Information Sciences, Almuzahmiyah, King Saud University.
    Khaan, Zahoorali
    Faculty of Engineering, Dalhousie University, Halifax, NS.
    Qasim, Umar
    University of Alberta, Edmonton.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Delay and energy consumption analysis of priority guaranteed MAC protocol for wireless body area networks2017In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 23, no 4, p. 1249-1266Article in journal (Refereed)
    Abstract [en]

    Wireless body area networks are captivating growing interest because of their suitability for wide range of applications. However, network lifetime is one of the most prominent barriers in deploying these networks for most applications. Moreover, most of these applications have stringent QoS requirements such as delay and throughput. In this paper, the modified superframe structure of IEEE 802.15.4 based MAC protocol is proposed which addresses the aforementioned problems and improves the energy consumption efficiency. Moreover, priority guaranteed CSMA/CA mechanism is used where different priorities are assigned to body nodes by adjusting the data type and size. In order to save energy, a wake-up radio based mechanism to control sleep and active modes of body sensors are used. Furthermore, a discrete time finite state Markov model to find the node states is used. Analytical expressions are derived to model and analyze the behavior of average energy consumption, throughput, packet drop probability, and average delay during normal and emergency data. Extensive simulations are conducted for analysis and validation of the proposed mechanism. Results show that the average energy consumption and delay are relatively higher during emergency data transmission with acknowledgment mode due to data collision and retransmission.

  • 11.
    Su, Guanming
    et al.
    Dolby Labs, Sunnyvale, CA.
    Su, Xiao
    Computer Engineering, San José State University.
    Bai, Yan
    Institute of Technology, University of Washington Tacoma.
    Wang, Mea
    Department of Computer Science, University of Calgary.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Wang, Haohong
    TCL Research America, San Jose.
    QoE in video streaming over wireless networks: perspectives and research challenges2016In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 22, no 5, p. 1571-1593Article in journal (Refereed)
    Abstract [en]

    The deployment of 3G/LTE networks and advancements in smart mobile devices had led to high demand for multimedia streaming over wireless network. The rapid increasing demand for multimedia content poses challenges for all parties in a multimedia streaming system, namely, content providers, wireless network service providers, and smart device makers. Content providers and mobile network service providers are both striving to improve their streaming services while utilizing advancing technologies. Smart device makers endeavor to improve processing power and displays for better viewing experience. Ultimately, the common goal shared by content providers, network service providers, and smart device manufactures is to improve the QoE for users. QoE is both an objective and a subjective metric measuring the streaming quality experience by end users. It may be measured by streaming bitrate, playback smoothness, video quality metrics like Peak to Signal Noise Ratio, and other user satisfaction factors. There have been efforts made to improve the streaming experiences in all these aspects. In this paper, we conducted a survey on existing literatures on QoE of video streaming to gain a deeper and more complete understanding of QoE quality metrics. The goal is to inspire new research directions in defining better QoE and improving QoE in existing and new streaming services such as adaptive streaming and 3D video streaming

  • 12.
    Zhang, Changsen
    et al.
    College of Computer Science and Technology, Henan Polytechnic University, Jiaozuo, Henan.
    Chen, Pengpeng
    College of Computer Science and Technology, Henan Polytechnic University, Jiaozuo, Henan.
    Ren, Jianji
    College of Computer Science and Technology, Henan Polytechnic University, Jiaozuo, Henan.
    Wang, Xiaofeng
    Department of Electrical and Computer Engineering, The University of British Columbia, Vancouver.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A backoff algorithm based on self-adaptive contention window update factor for IEEE 802.11 DCF2017In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 23, no 3, p. 749-758Article in journal (Refereed)
    Abstract [en]

    The binary exponential backoff (BEB) mechanism is applied to the packet retransmission in lots of wireless network protocols including IEEE 802.11 and 802.15.4. In distributed dynamic network environments, the fixed contention window (CW) updating factor of BEB mechanism can’t adapt to the variety of network size properly, resulting in serious collisions. To solve this problem, this paper proposes a backoff algorithm based on self-adaptive contention window update factor for IEEE 802.11 DCF. In WLANs, this proposed backoff algorithm can greatly enhance the throughput by setting the optimal CW updating factor according to the theoretical analysis. When the number of active nodes varies, an intelligent scheme can adaptively adjust the CW updating factor to achieve the maximal throughput during run time. As a result, it effectively reduces the number of collisions, improves the channel utilization and retains the advantages of the binary exponential back-off algorithm, such as simplicity and zero cost. In IEEE 802.11 distributed coordination function (DCF) protocol, the numerical analysis of physical layer parameters show that the new backoff algorithm performance is much better than BEB, MIMD and MMS algorithm.

  • 13.
    Zhu, Nanhao
    et al.
    CETC Group, GCI Science and Technology Co.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A generic framework for energy evaluation on wireless sensor networks2016In: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 22, no 4, p. 1199-1220Article in journal (Refereed)
    Abstract [en]

    Due to reliance on batteries, energy consumption has always been of significant concern for sensor node networks. This work presents the design and implementation of a house-build experimental platform, named Energy Management System for Wireless Sensor Networks (EMrise) for the energy management and exploration on wireless sensor networks. Consisting of three parts, the SystemC-based simulation environment of EMrise enables the HW/SW co-simulation for energy evaluation on heterogeneous sensor networks. The hardware platform of EMrise is further designed to facilitate the realistic energy consumption measurement and calibration as well as accurate energy exploration. In the meantime, a generic genetic algorithm based optimization framework of EMrise is also implemented to automatically, quickly and intelligently fine tune hundreds of possible solutions for the given task to find the best suitable energy-aware tradeoffs

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