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  • 1501.
    Zhang, Baoxian
    et al.
    Research Center of Ubiquitous Sensor Networks, University of Chinese Academy of Sciences, Beijing.
    Jiao, Shenzhen
    Research Center of Ubiquitous Sensor Networks, University of Chinese Academy of Sciences, Beijing.
    Li, Cheng
    Electrical and Computer Engineering, Faculty of Engineering and Applied Science, Memorial University of Newfoundland, St. John's.
    Jiao, Zheng
    Research Center of Ubiquitous Sensor Networks, University of Chinese Academy of Sciences, Beijing.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Efficient location-based topology control algorithms for wireless ad hoc and sensor networks2016In: Wireless Communications & Mobile Computing, ISSN 1530-8669, E-ISSN 1530-8677, Vol. 16, no 14, p. 1943-1955Article in journal (Refereed)
    Abstract [en]

    Topology control is an efficient strategy for improving the performance of wireless ad hoc and sensor networks by building network topologies with desirable features. In this process, location information of nodes can be used to improve the performance of a topology control algorithm and also ease its operations. Many location-based topology control algorithms have been proposed. In this paper, we propose two location-assisted grid-based topology control (GBP) algorithms. The design objective of our algorithm is to effectively reduce the number of active nodes required to keep global network connectivity. In grid-based topology control, a network is divided into equally spaced squares (called grids). We accordingly design cross-sectional topology control algorithm and diagonal topology control algorithm based on different network parameter settings. The key idea is to build near-minimal connected dominating set for the network at the grid level. Analytical and simulation results demonstrate that our designed algorithms outperform existing work. Furthermore, the diagonal algorithm outperforms the cross-sectional algorithm

  • 1502.
    Zhang, Bo
    et al.
    Nanjing University of Posts and Telecommunications.
    Wang, Yufeng
    Nanjing University of Posts and Telecommunications.
    Wei, Li
    Nanjing University of Posts and Telecommunications.
    Jin, Qun
    Department of Human Informatics and Cognitive Sciences, Waseda University, Saitama.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    BLE mesh: A practical mesh networking development framework for public safety communications2018In: Tsinghua Science and Technology, ISSN 1007-0214, E-ISSN 1878-7606, Vol. 23, no 3, p. 333-346Article in journal (Refereed)
    Abstract [en]

    Owing to advanced storage and communication capabilities today, smart devices have become the basic interface between individuals and their surrounding environment. In particular, massive devices connect to one other directly in a proximity area, thereby enabling abundant Proximity Services (ProSe), which can be classified into two categories: public safety communication and social discovery. However, two challenges impede the quick development and deployment of ProSe applications. From the viewpoint of networking, no multi-hop connectivity functionality component can be directly operated on commercially off-the-shelf devices, and from the programming viewpoint, an easily reusable development framework is lacking for developers with minimal knowledge of the underlying communication technologies and connectivity. Considering these two issues, this paper makes a twofold contribution. First, a multi-hop mesh networking based on Bluetooth Low Energy (BLE) is implemented, in which a proactive routing mechanism with link-quality (i.e., received signal strength indication) assistance is designed. Second, a ProSe development framework called BLE Mesh is designed and implemented, which can provide significant benefits for application developers, framework maintenance professionals, and end users. Rich application programming interfaces can help developers to build ProSe apps easily and quickly. Dependency inversion principle and template method pattern allow modules in BLE Mesh to be loosely coupled and easy to maintain and update. Callback mechanism enables modules to work smoothly together and automation processes such as registration, node discovery, and messaging are employed to offer nearly zero-configuration for end users. Finally, based on the designed ProSe development kit, a public safety communications app called QuoteSendApp is built to distribute emergency information in close area without Internet access. The process illustrates the easy usability of BLE Mesh to develop ProSe apps.

  • 1503.
    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.

  • 1504.
    Zhang, Heng
    et al.
    School of Information Engineering, East China Jiaotong University.
    Liu, Yanli
    School of Information Engineering, East China Jiaotong University.
    Xiong, Nealnaixue
    Department of Business and Computer Science, Southwestern Oklahoma State University.
    Imran, Muhammad Al
    College of Computer and Information Sciences, Almuzahmiyah, King Saud University.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    An improved similarity based adaptive step size glowworm algorithm2015In: Journal of Internet Technology, ISSN 1607-9264, E-ISSN 2079-4029, Vol. 16, no 5, p. 905-914Article in journal (Refereed)
    Abstract [en]

    This paper presents the similarity based adaptive step size glowworm swarm optimization algorithm (SBASS-GSO), an improved version of glowworm swarm optimization algorithm (GSO). The standard GSO algorithm lacks unified metric standard to different problems in the selection of neighbor set, which makes the algorithm converge slowly because of improper selection. Because the step size s is fixed, the oscillation phenomenon may occur in local search space, which leads to inferior search accuracy In SBASS-GSO algorithm, we change neighborhood definition base on the similarity not on the distance. The neighborhood is selected by computing average similarity, which provides priori knowledge for the adaptive size s. The dynamic size s is useful for removing oscillation phenomenon and improving the convergence speed. Experimental results demonstrate the efficacy of the proposed glowworm algorithm in capturing multiple optima of a series of complex test functions, such as Zakharov and Sphere functions. We also provide some comparisons of SBASS-GSO with GSO and verify the superiority in the precision and convergence speed.

  • 1505.
    Zhang, Qingke
    et al.
    School of Computer Science and technology, Engineering Research Center of Digital Media Technology, Ministry of Education, Shandong University, Jinan.
    Liu, Weiguo
    School of Computer Science and technology, Engineering Research Center of Digital Media Technology, Ministry of Education, Shandong University, Jinan.
    Men, Xiangxu
    School of Computer Science and technology, Engineering Research Center of Digital Media Technology, Ministry of Education, Shandong University, Jinan.
    Jiang, Bo
    Shandong Provincial Key Laboratory of Network based Intelligent Computing, University of Jinan.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Vector coevolving particle swarm optimization algorithm2017In: Information Sciences, ISSN 0020-0255, E-ISSN 1872-6291, Vol. 394-395, p. 273-298Article in journal (Refereed)
    Abstract [en]

    In this paper, we propose a novel vector coevolving particle swarm optimization algorithm (VCPSO). In VCPSO, the full dimension of each particle is first randomly partitioned into several sub-dimensions. Then, we randomly assign either one of our newly designed scalar operators or learning operators to update the values in each sub-dimension. The scalar operators are designed to enhance the population diversity and avoid premature convergence. In addition, the learning operators are designed to enhance the global and local search ability. The proposed algorithm is compared with several other classical swarm optimizers on thirty-three benchmark functions. Comprehensive experimental results show that VCPSO displays a better or comparable performance compared to the other algorithms in terms of solution accuracy and statistical results.

  • 1506.
    Zhang, Shengzhi
    et al.
    Florida Institute of Technology, Melbourne, FL.
    Makke, Omar
    Ford Motor, Detroit, MI.
    Gusikhin, Oleg Yu
    Ford Motor, Detroit, MI.
    Shah, Ayush
    Ford Motor, Detroit, MI.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A security model for dependable vehicle middleware and mobile applications connection2018In: VEHITS 2018: Proceedings of the 4th International Conference on Vehicle Technology and Intelligent Transport Systems / [ed] Gusikhin O.,Helfert M., 2018, p. 379-386Conference paper (Refereed)
    Abstract [en]

    Nowadays automotive industry has been working on the connectivity between automobile and smartphones, e.g., Ford’s SmartDeviceLink, MirrorLink, etc. However, as the interoperability between the smartphone and automotive system increase, the security concern of the increased attack surface bothers the automotive industry as well as the security community. In this paper, we thoroughly study the attack vectors against the novel connection framework between automobile and smartphones, and propose a generic security model to implement a dependable connection to eliminate the summarized attack vectors. Finally, we present how our proposed model can be integrated into existing automotive framework, and discuss the security benefits of our model. Copyright

  • 1507.
    Zhang, Weizhe
    et al.
    School of Computer Science and Technology, Harbin Institute of Technology.
    Li, Xiong
    School of Computer Science and Technology, Harbin Institute of Technology.
    Xiong, Naixue
    Department of Business and Computer Science, Southwestern Oklahoma State University, Oklahoma, OK.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Android platform-based individual privacy information protection system2016In: Personal and Ubiquitous Computing, ISSN 1617-4909, E-ISSN 1617-4917, Vol. 20, no 6, p. 875-884Article in journal (Refereed)
    Abstract [en]

    With the popularity of mobile phones with Android platform, Android platform-based individual privacy information protection has been paid more attention to. In consideration of individual privacy information problem after mobile phones are lost, this paper tried to use SMS for remote control of mobile phones and providing comprehensive individual information protection method for users and completed a mobile terminal system with self-protection characteristics. This system is free from the support of the server and it can provide individual information protection for users by the most basic SMS function, which is an innovation of the system. Moreover, the protection mechanism of the redundancy process, trusted number mechanism and SIM card detection mechanism are the innovations of this system. Through functional tests and performance tests, the system could satisfy user functional and non-functional requirements, with stable operation and high task execution efficiency

  • 1508.
    Zhang, Wenbin
    et al.
    School of Mathematical Sciences, Yangzhou University, Jiangsu.
    Tang, Yang
    Key Laboratory of Advanced Control and Optimization for Chemical Processes, Ministry of Education, East China University of Science and Technology, Shanghai.
    Huang, Tingwen
    Texas A & M University at Qatar.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Consensus of Networked Euler-Lagrange Systems under Time-Varying Sampled-Data Control2018In: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 14, no 2, p. 535-544Article in journal (Refereed)
    Abstract [en]

    This paper is concerned with the consensus of multiple Euler-Lagrange systems with pulse-width modulated sampled-data control. Different from traditional sampled-data strategies, a pulse-modulated sampled-data strategy is developed to realize the consensus of multiple Euler-lagrange systems, in which a pulse function that can be distinct at different sampling instants is proposed to modulate the sampling interval. In addition, a new definition of average sampling interval, which is parallel to the average dwell time in switching control or average impulsive interval in impulsive control, is proposed to characterize the number of the updating of the sampling controller during some certain interval. The proposed average sampling interval makes our sampled-data strategy more suitable for a wide range of sampling signals. By utilizing the comparison principle, a sufficient criterion is obtained to guarantee the consensus of multiple Euler-Lagrange systems. The sufficient criterion is heavily dependent on the actual control duration time, the upper and lower bounds of the pulse function and the communication graph. Finally, a simulation example is presented to verify the applicability of the proposed results.

  • 1509.
    Zhang, Xiaojing
    et al.
    Department of Power Device, ABB AB, Corporate Research, Vasteras.
    Lindberg, Thomas
    Department of Engineering and Physics, Karlstad University.
    Xiong, N.
    School of Innovation, Design and Engineering, Malardalen University, Vasteras.
    Vyatkin, Valeriy
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Mousavi, Arash
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Cooling Energy Consumption Investigation of Data Center IT Room with Vertical Placed Server2017In: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, p. 2047-2052Article in journal (Refereed)
    Abstract [en]

    As energy consumption by cooling data center IT equipment can be over 40% of total energy consumption, efficient cooling for large data centers is essential for reducing operation costs. Modern data centers are complex systems involving IT facilities, power system, cooling and ventilation systems. In our previous work, literature study was made to investigate available data center energy consumption models; and energy consumption models for data center IT room with distributed air flow control were developed. In this paper, the models are further extended and developed to cover the combined distributed air flow control and vertical placed servers in raised floor ventilation system. Simulation of the three types of ventilation systems with Even load, Idle server and Uneven load scenarios showed that significant cooling energy consumed by a traditional ventilation system can be saved by applying the proposed new concept and method.

  • 1510.
    Zhang, Yi-Qing
    et al.
    Adaptive Networks and Control Laboratory, Department of Electronic Engineering, and the Center of Smart Networks and Systems, School of Information Science and Engineering, Fudan University.
    Li, Xiang
    Adaptive Networks and Control Laboratory, Department of Electronic Engineering, and the Center of Smart Networks and Systems, School of Information Science and Engineering, Fudan University.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Spectral Analysis of Epidemic Thresholds of Temporal Networks2017In: IEEE Transactions on Cybernetics, ISSN 2168-2267, E-ISSN 2168-2275Article in journal (Refereed)
    Abstract [en]

    Many complex systems can be modeled as temporal networks with time-evolving connections. The influence of their characteristics on epidemic spreading is analyzed in a susceptible-infected-susceptible epidemic model illustrated by the discrete-time Markov chain approach. We develop the analytical epidemic thresholds in terms of the spectral radius of weighted adjacency matrix by averaging temporal networks, e.g., periodic, nonperiodic Markovian networks, and a special nonperiodic non-Markovian network (the link activation network) in time. We discuss the impacts of statistical characteristics, e.g., bursts and duration heterogeneity, as well as time-reversed characteristic on epidemic thresholds. We confirm the tightness of the proposed epidemic thresholds with numerical simulations on seven artificial and empirical temporal networks and show that the epidemic threshold of our theory is more precise than those of previous studies.

  • 1511.
    Zhang, Yunquan
    et al.
    State Key Laboratory of Computer Architecture, Institute of Computing Technology, Chinese Academy of Sciences, Beijing.
    Cao, Ting
    State Key Laboratory of Computer Architecture, Institute of Computing Technology, Chinese Academy of Sciences, Beijing.
    Li, Shigang
    State Key Laboratory of Computer Architecture, Institute of Computing Technology, Chinese Academy of Sciences, Beijing.
    Tian, Xinhui
    Advanced Computer Systems Research Center, Institute of Computing Technology, Chinese Academy of Sciences, Beijing.
    Yuan, Liang
    State Key Laboratory of Computer Architecture, Institute of Computing Technology, Chinese Academy of Sciences, Beijing.
    Yia, Haipeng
    State Key Laboratory of Computer Architecture, Institute of Computing Technology, Chinese Academy of Sciences, Beijing.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Parallel Processing Systems for Big Data: A Survey2016In: Proceedings of the IEEE, ISSN 0018-9219, E-ISSN 1558-2256, Vol. 104, no 11, p. 2114-2136Article in journal (Refereed)
    Abstract [en]

    The volume, variety, and velocity properties of big data and the valuable information it contains have motivated the investigation of many new parallel data processing systems in addition to the approaches using traditional database management systems (DBMSs). MapReduce pioneered this paradigm change and rapidly became the primary big data processing system for its simplicity, scalability, and fine-grain fault tolerance. However, compared with DBMSs, MapReduce also arouses controversy in processing efficiency, low-level abstraction, and rigid dataflow. Inspired by MapReduce, nowadays the big data systems are blooming. Some of them follow MapReduce's idea, but with more flexible models for general-purpose usage. Some absorb the advantages of DBMSs with higher abstraction. There are also specific systems for certain applications, such as machine learning and stream data processing. To explore new research opportunities and assist users in selecting suitable processing systems for specific applications, this survey paper will give a high-level overview of the existing parallel data processing systems categorized by the data input as batch processing, stream processing, graph processing, and machine learning processing and introduce representative projects in each category. As the pioneer, the original MapReduce system, as well as its active variants and extensions on dataflow, data access, parameter tuning, communication, and energy optimizations will be discussed at first. System benchmarks and open issues for big data processing will also be studied in this survey.

  • 1512.
    Zhang, Zhongshan
    et al.
    University of Science and Technology, Beijing, Beijing Engineering and Technology Center for Convergence Networks and Ubiquitous Services, University of Science and Technology Beijing (USTB).
    Long, Keping
    University of Science and Technology, Beijing, Beijing Engineering and Technology Center for Convergence Networks and Ubiquitous Services, University of Science and Technology Beijing (USTB).
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Hanzo, Lajos
    University of Southampton, School of Electronics and Computer Science, University of Southanpton.
    Full-Duplex Wireless Communications: Challenges, Solutions, and Future Research Directions2016In: Proceedings of the IEEE, ISSN 0018-9219, E-ISSN 1558-2256, Vol. 104, no 7, p. 1369-1409Article in journal (Refereed)
    Abstract [en]

    The family of conventional half-duplex (HD) wireless systems relied on transmitting and receiving in different time slots or frequency subbands. Hence, the wireless research community aspires to conceive full-duplex (FD) operation for supporting concurrent transmission and reception in a single time/frequency channel, which would improve the attainable spectral efficiency by a factor of two. The main challenge encountered in implementing an FD wireless device is the large power difference between the self-interference (SI) imposed by the device’s own transmissions and the signal of interest received from a remote source. In this survey, we present a comprehensive list of the potential FD techniques and highlight their pros and cons. We classify the SI cancellation techniques into three categories, namely passive suppression, analog cancellation and digital cancellation, with the advantages and disadvantages of each technique compared. Specifically, we analyze the main impairments (e.g., phase noise, power amplifier nonlinearity, as well as in-phase and quadrature-phase (I/Q) imbalance, etc.) that degrading the SI cancellation. We then discuss the FD-based media access control (MAC)-layer protocol design for the sake of addressing some of the critical issues, such as the problem of hidden terminals, the resultant end-to-end delay and the high packet loss ratio (PLR) due to network congestion. After elaborating on a variety of physical/MAC-layer techniques, we discuss potential solutions conceived for meeting the challenges imposed by the aforementioned techniques. Furthermore, we also discuss a range of critical issues related to the implementation, performance enhancement and optimization of FD systems, including important topics such as hybrid FD/HD scheme, optimal relay selection and optimal power allocation, etc. Finally, a variety of new directions and open problems associated with FD technology are pointed out. Our hope is that this treatise will stimul- te future research efforts in the emerging field of FD communications.

  • 1513.
    Zhang, Zhongshan
    et al.
    University of Science and Technology, Beijing.
    Wang, Xiyuan
    University of Science and Technology, Beijing.
    Long, Keping
    University of Science and Technology, Beijing.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Hanzo, Lajos
    University of Southampton.
    Large-scale MIMO-based wireless backhaul in 5G networks2015In: IEEE wireless communications, ISSN 1536-1284, E-ISSN 1558-0687, Vol. 22, no 5, p. 58-66Article in journal (Refereed)
    Abstract [en]

    In order to enhance the attainable transmission rates to the levels specified by future wireless communications, a paradigm shift from conventional small-scale MIMO to large-scale (LS)-MIMO is highly desirable. LS-MIMO technology as a "cleanslate" approach is shown to be capable of dramatically increasing the area spectral efficiency (SE, as measured in bits per second per Hertz per square kilometer) while simultaneously improving the energy efficiency as measured in bits per Joule. Furthermore, the concept of LS-MIMO has established itself as a beneficial transmission/detection paradigm, thus substantially reducing the impact of interference relying on some advanced transmit precoding/ beamforming/detection techniques. This article is intended to offer a state-of-the-art survey on LS-MIMO research, to promote the discussion of its beneficial application areas and the research challenges associated with BF aided wireless backhaul, LS-MIMO channel modeling, signal detection, and so on. Additionally, a joint group power allocation and pre-beamforming scheme called JGPAPBF is proposed to substantially improve the performance of LS-MIMO-based wireless backhaul in heterogeneous networks. Our hope is that this article will stimulate future research efforts.

  • 1514.
    Zhao, Xiaoxing
    et al.
    Beijing University of Posts and Telecommunications.
    Qiao, Yuanyuan
    Beijing University of Posts and Telecommunications.
    Si, Zhongwei
    Beijing University of Posts and Telecommunications.
    Yang, Jie
    Beijing University of Posts and Telecommunications.
    Lindgren, Anders
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Prediction of user app usage behavior from geo-spatial data2016In: GeoRich '16: Proceedings of the Third International ACM SIGMOD Workshop on Managing and Mining Enriched Geo-Spatial Data, New York: ACM Digital Library, 2016, p. 37-42, article id 7Conference paper (Refereed)
    Abstract [en]

    In the era of mobile Internet, a vast amount of geo-spatial data allows us to gain further insights into human activities, which is critical for Internet Services Providers (ISP) to provide better personalized services. With the pervasiveness of mobile Internet, much evidence show that human mobility has heavy impact on app usage behavior. In this paper, we propose a method based on machine learning to predict users' app usage behavior using several features of human mobility extracted from geo-spatial data in mobile Internet traces. The core idea of our method is selecting a set of mobility attributes (e.g. location, travel pattern, and mobility indicators) that have large impact on app usage behavior and inputting them into a classification model. We evaluate our method using real-world network traffic collected by our self-developed high-speed Traffic Monitoring System (TMS). Our prediction method achieves 90.3% accuracy in our experiment, which verifies the strong correlation between human mobility and app usage behavior. Our experimental results uncover a big potential of geo-spatial data extracted from mobile Internet

  • 1515.
    Zhohov, Roman
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Minovski, Dimitar
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. InfoVista Sweden.
    Johansson, Per
    InfoVista Sweden.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Real-time Performance Evaluation of LTE for IIoT2018In: Proceedings of the 43rd IEEE Conference on Local Computer Networks (LCN) / [ed] Soumaya Cherkaoui, Institute of Electrical and Electronics Engineers (IEEE), 2018Conference paper (Refereed)
    Abstract [en]

    Industrial Internet of Things (IIoT) is claimed to be a global booster technology for economic development. IIoT brings bulky use-cases with a simple goal of enabling automation, autonomation or just plain digitalization of industrial processes. The abundance of interconnected IoT and CPS generate additional burden on the telecommunication networks, imposing number of challenges to satisfy the key performance requirements. In particular, the QoS metrics related to real-time data exchange for critical machine-to-machine type communication. This paper analyzes a real-world example of IIoT from a QoS perspective, such as remotely operated underground mining vehicle. As part of the performance evaluation, a software tool is developed for estimating the absolute, one-way delay in end-toend transmissions. The measured metric is passed to a machine learning model for one-way delay prediction based on LTE RAN measurements using a commercially available cutting-edge software tool. The achieved results prove the possibility to predict the delay figures using machine learning model with a coefficient of determination up to 90%.

  • 1516.
    Zhou, Biyu
    et al.
    Beijing Key Laboratory of Mobile Computing and Pervasive Device, Institute of Computing Technology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Bejing.
    Zhang, Fa
    Key Laboratory of Intelligent Information Processing, Institute of Computing Technology, Chinese Academy of Sciences, Beijing.
    Wang, Lin
    SnT, University of Luxembourg.
    Hou, Chenying
    Beijing Key Laboratory of Mobile Computing and Pervasive Device, Institute of Computing Technology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Bejing.
    Anta, Antonio Fernández
    IMDEA Networks Institute.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Wang, Youshi
    Beijing Key Laboratory of Mobile Computing and Pervasive Device, Institute of Computing Technology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Bejing.
    Wu, Jie
    Department of Computer and Information Sciences, Temple University, Philadephia.
    Liu, Zhiyong
    State Key Laboratory for Computer Architecture, Beijing Key Laboratory of Mobile Computing and Pervasive Device, Institute of Computing Technology, Chinese Academy of Sciences, Beijing.
    HDEER: A Distributed Routing Scheme for Energy-Efficient Networking2016In: IEEE Journal on Selected Areas in Communications, ISSN 0733-8716, E-ISSN 1558-0008, Vol. 34, no 5, p. 1713-1727Article in journal (Refereed)
    Abstract [en]

    The proliferation of new online Internet services has substantially increased the energy consumption in wired networks, which has become a critical issue for Internet service providers. In this paper, we target the network-wide energy-saving problem by leveraging speed scaling as the energy-saving strategy. We propose a distributed routing scheme-HDEER-to improve network energy efficiency in a distributed manner without significantly compromising traffic delay. HDEER is a two-stage routing scheme where a simple distributed multipath finding algorithm is firstly performed to guarantee loop-free routing, and then a distributed routing algorithm is executed for energy-efficient routing in each node among the multiple loop-free paths. We conduct extensive experiments on the NS3 simulator and simulations with real network topologies in different scales under different traffic scenarios. Experiment results show that HDEER can reduce network energy consumption with a fair tradeoff between network energy consumption and traffic delay.

  • 1517.
    Zhou, Fanfu
    et al.
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Qi, Zhengwei
    School of Software, Shanghai Jiao Tong University, Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Yao, Jianguo
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Guan, Haibing
    School of Software, Shanghai Jiao Tong University, Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    D2FL: design and Implementation of Distributed Dynamic Fault Localization2018In: IEEE Transactions on Dependable and Secure Computing, ISSN 1545-5971, E-ISSN 1941-0018, Vol. 15, no 3, p. 378-392Article in journal (Refereed)
    Abstract [en]

    Compromised or misconfigured routers have been a major concern in large-scale networks. Such routers sabotage packet delivery, and thus hurt network performance. Data-plane fault localization (FL) promises to solve this problem. Regrettably, the path-based FL fails to support dynamic routing, and the neighbor-based FL requires a centralized trusted administrative controller (AC) or global clock synchronization in each router and introduces storage overhead for caching packets. To address these problems, we introduce a dynamic distributed and low-cost model, D2FL. Using random 2-hop neighborhood authentication, D2FL supports volatile path without the AC or global clock synchronization. Besides, D2FL requires only constant tens of KB for caching which is independent of the packet transmission rate. This is much less than the cache size of DynaFL or DFL which consumes several MB. The simulations show that D2FL achieves low false positive and false negative rate with no more than 3% bandwidth overhead. We also implement an open source prototype and evaluate its effect. The result shows that the performance burden in user space is less than 10% with the dynamic sampling algorithm. 

  • 1518.
    Zhou, Lina
    et al.
    Information Systems Department, UMBC, Baltimore.
    Pan, Shimei
    Information Systems Department, UMBC, Baltimore.
    Wang, Jianwu
    Information Systems Department, UMBC, Baltimore.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Machine Learning on Big Data: Opportunities and Challenges2017In: Neurocomputing, ISSN 0925-2312, E-ISSN 1872-8286, Vol. 237, p. 350-361Article in journal (Refereed)
    Abstract [en]

    Machine learning (ML) is continuously unleashing its power in a wide range of applications. It has been pushed to the forefront in recent years partly owing to the advert of big data. ML algorithms have never been better promised while challenged by big data. Big data enables ML algorithms to uncover more fine-grained patterns and make more timely and accurate predictions than ever before; on the other hand, it presents major challenges to ML such as model scalability and distributed computing. In this paper, we introduce a framework of ML on big data (MLBiD) to guide the discussion of its opportunities and challenges. The framework is centered on ML which follows the phases of preprocessing, learning, and evaluation. In addition, the framework is also comprised of four other components, namely big data, user, domain, and system. The phases of ML and the components of MLBiD provide directions for the identification of associated opportunities and challenges and open up future work in many unexplored or under explored research areas.

  • 1519.
    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

  • 1520.
    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.
    EMrise: An Energy Management Platform for WSNs/WBANs2016In: Energy Management in Wireless Cellular and Ad-hoc Networks, Encyclopedia of Global Archaeology/Springer Verlag, 2016, p. 367-395Chapter in book (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 EMrise (Energy Management System for Wireless Sensor Networks) 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 GA (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.

  • 1521.
    Zhu, Xudong
    et al.
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Li, Jun
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Gao, Xiaofeng
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Wu, Fan
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Chen, Guihai
    Shanghai Key Laboratory of Scalable Computing and Systems, Department of Computer Science and Engineering, Shanghai Jiao Tong University.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A distributed approximation for multi-hop clustering problem in wireless sensor networks2016In: 2015 IEEE Global Communications Conference (GLOBECOM): San Diego, CA, 6-10 Dec 2015, Piscataway, NJ: IEEE Communications Society, 2016, article id 7416941Conference paper (Refereed)
    Abstract [en]

    In wireless sensor networks (WSNs), there is no predefined infrastructure. Nodes need to frequently flood messages to discover routes, which badly decreases the network performance. To overcome such drawbacks, WSNs are often grouped into several disjointed clusters, each with a representative cluster head (CH) in charge of the routing process. In order to further improve the efficiency of WSNs, it is crucial to find a cluster partition with minimum number of clusters and the distance between each node to its corresponding CH can be bounded by a constant number of hops. Finding such a partition is defined as minimum d-hop cluster head set (d-MCHS) problem, which is proved to be NP-hard. In this paper, we propose a distributed approximation algorithm, named d^2-Cluster, to address d-MCHS problem and prove that the approximation ratio of d^2-Cluster under unit disk graph (UDG) is a constant factor \lambda which is related to d. To the best of our knowledge, it is the first constant approximation ratio for d-MDS problem in UDG

  • 1522.
    Zhuang, Hui
    et al.
    Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology.
    Li, Jintao
    Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology.
    Geng, Weibiao
    Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology.
    Dai, Xiaoming
    Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology.
    Zhang, Zhogshan
    Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology.
    Vasilakos, Athanasios
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Duplexer design and implementation for self-interference cancellation in full-duplex communications2016In: European Signal Processing Conference, EUSIPCO 2016, Piscataway, NJ: IEEE Computer Society Digital Library, 2016, p. 125-129, article id 7760223Conference paper (Refereed)
    Abstract [en]

    The full-duplex (FD) based devices are capable of concurrently transmitting and receiving signals with a single frequency band. However, a severe self-interference (SI) due to the large difference between the power of the devices' own transmission and that of the signal of interest may be imposed on the FD based devices, thus significantly eroding the received signal-to-interference-plus-noise ratio (SINR). To implement the FD devices, the SI power must be sufficiently suppressed to provide a high-enough received SINR for satisfying the decoding requirement. In this paper, the design and implementation of the duplexer for facilitating SI cancellation in FD based devices are investigated, with a new type of duplexer (i.e. an improved directional coupler) designed and verified. It is shown that the SI suppression capability may be up to 36 dB by using the proposed design, which is much higher than that attainable in the commonly designed ferrite circulator

  • 1523.
    Åhlund, Andreas
    et al.
    Umeå University, Department of Computer Science.
    Mitra, Karan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Johansson, Dan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Context-aware application mobility support in pervasive computing environments2009In: Proceedings of the 6th International Conference on Mobile Technology, Application & Systems : 2009, Nice, France, September 02 - 04, 2009, New York: ACM Digital Library, 2009Conference paper (Refereed)
    Abstract [en]

    In the future, application mobility can play a crucial role and prove to be an enabler for next generation distributed applications. Application mobility lets an application follow the users while they roam between networks using several devices. In order to achieve seamless application mobility, several issues need to be considered such as device heterogeneity, GUI-adaptation and application loss. Thus, in this paper our contributions are two-fold. Firstly, we present our novel architecture called the Application Mobility Manager (A2M) which provides seamless application mobility. The proposed architecture is context-aware and decentralized. Finally, we present a novel application called the Mobile YouTube Player which is capable of moving between heterogeneous devices and provide users with seamless video experience. We validate the proposed system through rigorous experimentation and user studies based on the real-world test bed and prototype implementation. The results clearly validate that the proposed system can support seamless application mobility.

  • 1524.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Extended mobile IP and support for global connectivity in hybrid networks2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mobility is an essential and necessary feature for roaming users who connect to wireless networks via access points. Access points may have different capabilities, be connected to different networks and be installed by different providers. A mobile host will discover multiple access points in this environment. A mobile host should be able to use the best available connectivity to communicate with a correspondent host and perhaps use multiple connections for different hosts. In areas with wireless local area network access, pockets with limited or no coverage could exist. Such restricted connectivity could be compensated by neighbor hosts who form an ad hoc network and relay packets until they reach an access point. This thesis describes and discusses the proposed solutions towards enabling and supporting connectivity in wireless access networks. In the proposed solutions the network layer software will evaluate and decide which wireless network connections to use. This thesis proposes a Running Variance Metric (RVM) and a Relative Network Load (RNL) as performance metrics to classify the traffic load of access points in wireless access networks. RVM and RNL can be efficiently used for infrastructure networks and ad hoc networks. This thesis proposes an extension to Mobile IP in order to enable mobile hosts to use multiple care-of addresses simultaneously. These extensions enhance network connectivity by enabling the mobile host, the home agent and correspondent hosts to evaluate and select the best connection. The proposed extension to Mobile IP is called Multihomed Mobile IP to emphasize support for multiple connections for a mobile host at the same time. This thesis describes a proposed gateway architecture that integrates wired IP networks with ad hoc networks. Routes between a mobile host and gateways are maintained continuously where multi-hop ad hoc connections are supported. Communication between peers in ad hoc networks is based on reactive ad hoc routing. Mobile hosts moving between ad hoc networks are supported by Multihomed Mobile IP. This thesis describes developed prototypes and simulation results to validate multihomed Mobile IP and the gateway architecture which integrates ad hoc networks and wired IP networks.

  • 1525.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Supporting global connectivity in heterogeneous IP networks2002Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Mobility of user devices connecting to the Internet is of major interest in today's research in networking. Users with portable devices, like laptops and personal digital assistants (PDA), connecting to foreign networks in the Internet want the same functionality as when connected to the home network as well as accessibility through the home IP address. For the users as well as for the applications, network mobility should be transparent. To achieve this transparency, the Mobile IP is deployed. Connecting wireless devices through an access point for network access enables mobility. Geographical areas are covered with wireless high bandwidth connections, creating so-called hot spot areas. The access points may have different capabilities, be connected to different networks and be installed by different providers. A mobile host will sense multiple access points in this environment. To make use of the dynamic capability, a device should be able to use the best available connectivity for a network flow and perhaps different connections for different flows. In hot spot areas it may be difficult to cover everything with good radio coverage, and therefore a mobile host may have to use an intermediate, peer mobile host for connectivity to an access point. Also, co-operating mobile users who require connectivity between their devices, should be able to quickly and easily establish a multi-hop ad hoc network between them. This thesis proposes and describes a number of solutions towards enhancing network connectivity in wireless broadband network areas, where the networking software will evaluate and decide which wireless network connections to use. Multi-hop ad hoc connections can be used between peers and in the connecting to access points. Modifications are proposed to Mobile IP to manage multihoming of a mobile host simultaneously connecting it to multiple access points. The connectivity between mobile hosts and access points is evaluated to enable usage of the best connections. The mobile host, the home agent and the correspondent host are able to decide on which network connections to use. A gateway is proposed to enable a reactive ad-hoc routing protocol to interoperate with wired IP networks and to support mobility of hosts between ad hoc networks.

  • 1526.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brännström, Robert
    Andersson, Karl
    Tjernström, Örjan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Multimedia flow mobility in heterogeneous networks using multihomed mobile IPv62006In: Proceedings of the 4th International Conference on Advances in Mobile Computing and Multimedia: MoMM 2006, 2006Conference paper (Refereed)
    Abstract [en]

    Communication in next generation networks will use multiple access technologies, creating a heterogeneous network environment. To enable end-user terminals to move between access networks with minimal disruption, the terminals should be able to maintain multiple active network connections. Such a multihomed mobile host will experience different capabilities and coverage area depending on the access technologies. This paper proposes and evaluates an extension to Mobile IPv6 enabling multihoming, regardless of the access technology. Mobility of multimedia communication in this environment should adapt to changing conditions and be base on dynamic measurements and user preferences. The proposed architecture gives opportunities for mobile multimedia applications to use multiple access networks simultaneously and the possibility to move individual flows. Media flows are identified by destination IP address, protocol and port number. Results from a real world prototype are presented using three different wireless access technologies: 802.11, UMTS and 802.16-2004.

  • 1527.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brännström, Robert
    Andersson, Karl
    Tjernström, Örjan
    Port-based multihomed mobile IPv6 for heterogeneous networks2006In: Proceedings: the 31st IEEE Conference on Local Computer Networks, LCN 2006 : Tampa, Florida, U.S.A., November 14 - 16, 2006, Piscataway, NJ: IEEE Communications Society, 2006, p. 567-568Conference paper (Refereed)
    Abstract [en]

    Future wireless networks are expected to be based on coexistence of multiple different access network technologies. Mobile devices will then be equipped with multiple wireless interfaces enabling connectivity via multiple architectures. Different wireless techno-logies differ widely considering their capabilities and coverage. This requires a mobile node to maintain multiple active connections depending on the appli-cations used and available access networks. To enable this, a mobile node needs to be multihomed and able to direct traffic flows via different interfaces. This paper describes a proposal extending Mobile IPv6 with multihoming functionality. Multihoming is managed using IP address, protocol and port number.

  • 1528.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brännström, Robert
    Zaslavsky, Arkady
    A multihoming approach to mobile IP2003In: Swedish National Computer Networking Workshop - Proceedings: SNCNW 2003, Stockholm, 2003Conference paper (Other academic)
    Abstract [en]

    Mobile IP is the standard for mobility management in IP networks. With today's emerging possibilities within wireless broadband communication, mobility within networks will increase. New applications and protocols will be created and Mobile IP is important to this development, since Mobile IP support can be used to allow mobile hosts to move between networks with maintained connectivity. This article describes multihomed Mobile IP enabling mobile hosts to register multiple care-of addresses at the home agent, to enhance the performance of wireless network connectivity. Flows can be load-balanced between care-of addresses to achieve a more reliable connectivity. A prototype is also described.

  • 1529.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brännström, Robert
    Zaslavsky, Arkady
    Agent selection strategies in wireless networks with multihomed mobile ip2004In: Service Assurance with Partial and Intermittent Resources: First International Workshop, SAPIR 2004, Fortaleza, Brazil, August 1-6, 2004. Proceedings / [ed] Petre Dini; Pascal Lorenz; José Neuman DeSouza, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2004, p. 197-206Conference paper (Refereed)
    Abstract [en]

    Mobile IP is a proposed standard for mobility management in IP networks. With today’s emerging possibilities within wireless broadband communication, mobility within networks will increase. New applications and protocols will be created and Mobile IP is important to this development, since Mobile IP support is needed to allow mobile hosts to move between networks with maintained connectivity. This article describes multihomed Mobile IP enabling mobile hosts to register multiple care-of addresses at the home agent, to enhance the performance of wireless network connectivity. A prototype is described and a simulator evaluation shows the performance of our approach.

  • 1530.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brännström, Robert
    Zaslavsky, Arkady
    M-mip: extended mobile ip to maintain multiple connections to overlapping wireless access networks2005In: Networking - ICN 2005: 4th International Conference on Networking, Reunion Island, France, April 17 - 21, 2005; / [ed] Pascal Lorenz, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2005, p. 204-213Conference paper (Refereed)
    Abstract [en]

    In future wireless access networks, connectivity to wired infrastructure will be provided through multiple access points with possibly different capabilities and utilization. The demand for increased network performance requires the ability to predict the best overall performance of those access points and to switch access point when the performance changes. Then there is the demand for mobility between networks with maintained connectivity which requires the ability to switch the point of attachment. We propose Multihomed Mobile IP, enabling performance discovery at the networks layer and the capability to decide what AP to use. Mobile IP support is needed to allow mobile hosts to move between networks with maintained connectivity. Multihomed Mobile IP enables mobile hosts to register multiple care-of addresses at the home agent, to enhance the performance of wireless network connectivity. This article describes a simulator evaluation of multihomed Mobile IP.

  • 1531.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brännström, Robert
    Zaslavsky, Arkady
    Running variance metric for evaluating performance of wireless ip networks in the mobilecity testbed2005In: Proceedings: First International Conference on Testbeds and Research Infrastructures for the Development of Networks and Communities : Trento, Italy, February 23 - 25, 2005 / [ed] Roberto Battiti, Los Alamitos, Calif: IEEE Computer Society Press , 2005, p. 120-127Conference paper (Refereed)
    Abstract [en]

    This paper proposes and analyzes a Running Variance Metric performance measurement of wireless local area networks and its formal aspects. Our approach evaluates the performance of wireless local area networks in infrastructure mode as well as in ad hoc mode. The Running Variance Metric is used to discover relative traffic loads of available access-points/gateways at the network layer in order to provide connectivity to the wired network. The paper discusses a simulation study. The simulation results demonstrate the usefulness and efficiency of the Running Variance Metric to evaluate the utilization of available access-points/gateways. It is also shown that this metric can be used for hop-analysis in multi-hop ad hoc wireless networks.

  • 1532.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brännström, Robert
    Zaslavsky, Arkady
    Traffic load metrics for multihomed mobile IP and global connectivity2006In: Telecommunications Systems, ISSN 1018-4864, E-ISSN 1572-9451, Vol. 33, no 1-3, p. 155-185Article in journal (Refereed)
    Abstract [en]

    Support for host mobility an essential and necessary feature for roaming users who connect to wireless networks via access points. Access points may have different capabilities, be connected to different networks and be installed by different providers. A mobile host will discover multiple access points in this environment. In such an environment, a mobile host should be able to use the best available connection to communicate with a correspondent host and perhaps use multiple connections for different hosts. In areas with wireless local area network access, pockets with limited or no coverage could exist. Such restricted connectivity could be compensated by neighbor hosts who form an ad hoc network and relay packets until they reach an access point. This paper describes and discusses a proposed solution towards enabling and supporting connectivity in wireless networks. In the proposed solution the network layer software will evaluate and decide which wireless network connections to use. A Running Variance Metric (RVM) and a Relative Network Load(RNL) are used to measure the traffic load of access points in wireless access networks. RVM and RNL can be efficiently used for both infrastructure networks and ad hoc networks. Multihomed Mobile IP (M-MIP) is an extension of Mobile IP that enables mobile hosts to use multiple care-of addresses simultaneously. The extension enhances network connectivity by enabling the mobile host, the home agent and correspondent hosts to evaluate and select the best connection. A proposed gateway architecture using M-MIP that integrates wired IP networks with ad hoc networks is described. The M-MIP and gateway architecture using the RVM and RNL metrics have been validated with simulation studies and results are presented.

  • 1533.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Börjesson, Mikael
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Pettersson, Jan
    Brännström, Robert
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Larsson, Roger
    Johansson, Dan
    Granlund, Daniel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Project: Sense Smart City2010Other (Other (popular science, discussion, etc.))
    Abstract [en]

    Sense Smart City is a Swedish project designed to conduct research, create new business opportunities and sustainably increase ICT research and innovation capability with specific objective to make urban cities/areas "smarter". The project will generate new and better ICT solutions, that instrument urban areas to gather and combine information (energy, traffic, weather, events, activities, needs and oppinions) continously as well as "on-demand". This will enable city environments to become "smarter", as more adaptive and supportive environment, for its inhabitants and visitors - people as well as organisations.

  • 1534.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Toffia, Mario
    Luleå tekniska universitet.
    Elf, Stefan
    Luleå tekniska universitet.
    Nordmark, Håkan
    Luleå tekniska universitet.
    A framework for adaptive applications2000Conference paper (Other academic)
    Abstract [en]

    The adaptive applications framework presented here aims at enabling hosts in a network to share objects such as applications or data. The framework consists of a set of components needed at each host in the network. They are the repository, the monitor, and the mobile agents. The repository acts as a database for storage of objects and object semantics. An adaptive application, which itself is an object, first tries to access an object from the local repository. If it is not found, the search is extended to the repositories of co-operating hosts by the use of mobile agents. An object or a proxy object is returned to the requester. The application can be executed on the local host or on the remote host depending on predefined network and host load conditions. The framework that has been prototyped will form a base for further work, which includes exploring the use of semantic modelling for pre-caching and intelligent download of resources.

  • 1535.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Wallin, Stefan
    Andersson, Karl
    Brännström, Robert
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A service level model and Internet mobility monitor2008In: Telecommunications Systems, ISSN 1018-4864, E-ISSN 1572-9451, Vol. 37, no 1-3, p. 49-70Article in journal (Refereed)
    Abstract [en]

    Mobility is gaining a tremendous interest among Internet users and wireless access networks are increasingly being installed to enable mobile usage. Internet mobility requires solutions to move between access networks with maintained network connectivity. Seamless mobility in turn means that the experience of using a service is unaffected while being mobile. Communication in next generation networks will use multiple access technologies, creating a heterogeneous network environment. Further, roaming between network service providers may take place. To enable mobile nodes to move between access networks within as well as between network service providers with minimal disruption, nodes should be able to maintain multiple active network connections. With the usage of multihomed nodes, seamless mobility can be achieved in already installed infrastructures, not providing mobility support. Mobility in heterogeneous access networks also requires network selections that scale for services. In this article we propose an architecture where application service providers and network service providers define service levels to be used by a mobile node and its user. The user selects a service and the service level from an application service provider. When performing access network selection, information received as part of an application service level will be used to find a network that supports the service required. The performance of available access networks will be monitored and considered when making the decision. Our proposed architecture provides solutions to move flows between interfaces in real-time based on network performance, quality of service signalling to correspondent nodes, and cancellation of flows to give way for more important traffic.

  • 1536.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Extending global IP connectivity for ad hoc networks2003In: Telecommunications Systems, ISSN 1018-4864, E-ISSN 1572-9451, Vol. 24, no 2-4, p. 221-250Article in journal (Refereed)
    Abstract [en]

    Ad hoc networks have thus far been regarded as stand-alone networks without assumed connectivity to wired IP networks and the Internet. With wireless broadband communications and portable devices with appropriate CPU, memory and battery performance, ad hoc connectivity will become more feasible and demand for global connectivity through ad hoc networking is likely to rapidly grow. In this paper we propose an algorithm and describe a developed prototype for connectivity between an ad hoc network running the ad hoc on-demand distance-vector protocol and a wired IP network where mobile IP is used for mobility management. Implementation issues and performance metrics are also discussed.

  • 1537.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Integration of ad hoc network and IP network capabilities for mobile hosts2003In: 10th International Conference on Telecommunications: ICT 2003 ; February 23 - March 1, 2003, Sofitel Coralia Maeva Beach Hotel, Tahiti, Papeete, French Polynesia, Piscataway, NJ: IEEE Communications Society, 2003, Vol. 1, p. 482-489Conference paper (Refereed)
    Abstract [en]

    Mobility of user devices connecting to the Internet is of major interest in today’s research in networking. Users with portable devices, like laptops and personal digital assistants (PDA), connecting to foreign networks in the Internet want the same functionality as when connected to the home network, as well as accessibility through the home IP address. Ad hoc networking is also of major importance for connectivity between communicating mobile hosts without backbone infrastructure and for connectivity to access points. For the users as well as for the applications, network mobility should be transparent. The usage of the ad hoc network or the wired IP network should also be managed by the networking software and hidden from applications and users. In this paper we propose and describe an integrated connectivity solution and its software implementation between an ad hoc network running the Ad Hoc On- Demand Distance-Vector Protocol and a wired IP network where Mobile IP is used for mobility management. With the usage of ad hoc networking, a mobile host will be able to use multiple foreign networks to enhance the communication performance. A proposal to multihomed Mobile IP is presented to achieve this.

  • 1538.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    "Mobile city" ad hoc wireless network support for regional communities2001In: Proceedings: The Path to 4G Mobile, 2001Conference paper (Refereed)
  • 1539.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Multihoming with mobile IP2003In: High-Speed Networks and Multimedia Communications: 6th IEEE International Conference ; proceedings / HSNMC 2003, Estoril, Portugal, July 23 - 25, 2003 / [ed] Mário Marques Freire, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2003, p. 235-243Conference paper (Refereed)
    Abstract [en]

    Mobile IP is the standard for mobility management in IP networks. With today’s emerging possibilities within wireless broadband communication, mobility within networks will increase. New applications and protocols will be created and Mobile IP is important to this development, since Mobile IP support is needed to allow mobile hosts to move between networks with maintained connectivity. This article describes multihomed Mobile IP enabling mobile hosts to register multiple care-of addresses at the home agent, to enhance the performance of wireless network connectivity. Flows can be loadbalanced between care-of addresses to achieve a more reliable connectivity. A prototype is also described.

  • 1540.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Software solutions to Internet connectivity in mobile ad hoc networks2002In: Product focused software process improvement: 4th international conference ; proceedings / [ed] Markku Oivo, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2002, p. 559-571Conference paper (Refereed)
    Abstract [en]

    In recent years wireless Internet access and wireless communications between peers have become the focus of intensive research efforts in various areas of information and communication technologies. Mobility aspects, software development and support for mobile users are currently of major interest within this research area. The Mobile IP protocol is deployed for mobility management of hosts moving between networks. Ad hoc routing is also of major importance for connectivity between communicating mobile hosts without backbone infrastructure. In this paper we propose and describe an integrated connectivity solution and its software implementation between an ad hoc network running the Ad Hoc On-Demand Distance-Vector Protocol (AODV) and a wired IP network where Mobile IP is used for mobility management. The article also describes a project called Mobile City in which our software solutions and support infrastructure are tested and validated.

  • 1541.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Support for wireless connectivity in hot spot areas2002In: MOST: Technology for Mobile Society: MOST International Conference. Proceedings / [ed] Mieczysław R Muraszkiewicz, Warsaw: Most Press , 2002Conference paper (Refereed)
  • 1542.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Wireless network support for connectivity in regional communities2001In: Steps towards the information society of the future: conference proceedings ; International Conference on Emerging Telecommunications, and Workshop "How to Avoid the E-Learning Gap in Central and East European Countries?", 17 - 19 October, 2001, [Košice, Slovakia] / [ed] František Jakab, Košice: Nordic Centre for Welfare and Social Issues (NVC), 2001Conference paper (Refereed)
  • 1543.
    Åhlund, Christer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Matskin, M.
    Supporting mobile business applications in hot spot areas with pervasive infrastructure2002In: M-business 2002: evolution sceniarios for emerging mobile commerce services ; the 1st International Conference on Mobile Business ; 8 - 9 July 2002, Athens, Greece, Athens, 2002Conference paper (Refereed)
  • 1544.
    Ödling, Ola
    et al.
    Erisoft AB, Sweden.
    Wallin, Stefan
    Erisoft AB, Sweden.
    Building MIB Applications1994In: IEEE Network Operations and Management Symposium: Symposium Record : Wednesday, February 16: Sessions 11 - 20, Piscataway, NJ: IEEE Communications Society, 1994, Vol. 2, p. 565-575Conference paper (Refereed)
  • 1545.
    CSEE 2001: Second Annual Conference on Computer Science and Electrical Engineering, Luleå, Sweden May 21-22: Conference Proceedings2001Report (Other academic)
    Abstract [en]

    The second Annual Symposium on Computer Science and Electrical Engineering, CSEE'2001, was held in Luleå, Sweden on May 21-22, 2001. One objective was to give Ph.D. students an opportunity to present their ongoing work. The symposium also provided a forum for an exchange of ideas between researchers involved in theoretical as well as experimental and applied research. Papers concerning important aspects of computers and their use in systems, where presented.

  • 1546.
    CSEE2002: Second Annual Conference on Computer Science and Electrical Engineering, Luleå, Sweden May 27-28: Conference Proceedings2002Report (Other academic)
    Abstract [en]

    The third Annual Symposium on Computer Science and Electrical Engineering, CSEE'2002, was held in Luleå, Sweden on May 27-28, 2002. One objective was to give Ph.D. students an opportunity to present their ongoing work. The symposium also provided a forum for an exchange of ideas between researchers involved in theoretical as well as experimental and applied research. Papers concerning important aspects of computers and their use in systems, where presented.

  • 1547.
    Brogle, Marc (Editor)
    University of Bern.
    Osipov, Evgeny (Editor)
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Braun, Torsten (Editor)
    University of Bern.
    Heijenk, Geert (Editor)
    University of Twente.
    Fourth ERCIM workshop on e-mobility2010Report (Other academic)
    Abstract [en]

    ERCIM, the European Research Consortium for Informatics and Mathematics, aims to foster collaborative work within the European research community and to increase co-operation with European industry. In the ERCIM eMobility workshop, current progress and future developments in the area of eMobility should be discussed and the existing gap between theory and application closed. This volume contains all accepted papers of the fourth eMobility workshop, which has been held in Luleå, Sweden, on May 31, 2009. Papers from different areas have been selected for this workshop. The contributions discuss several topics of the ERCIM eMobility working group including, testbeds for mobile networks, performance optimization for cellular networks, QoS in V2B communication, reliability in ad-hoc networks, distributed resource discovery and use, traffic generation models for wireless networks, IMS clients, ICT support for mobility, VANETs, and mobile video conferencing.At this point, we want to thank all authors of the submitted papers and the members of the international program committee for their contribution to the success of the event and the high quality program. The proceedings are divided into two sections, full papers and short papers. While the latter present work in progress and ongoing research, the full papers have been carefully selected in a peer review process. The reviewers evaluated all papers and sent the authors the comments on their work.The invited talks featured presentations of different European research projects: ELVIRE presented by Marc Brogle, EU-Mesh presented by Vasilios Siris, Frederica presented by Kurt Baumann, GINSENG presented by Marilia Curado, Socrates presented by Hans van den Berg, Winemo presented by Yevgeni Koucheryavy, and Wisebed presented by Torsten Braun.Luleå University of Technology is the northernmost university of technology in Scandinavia and with world-class research and education. Its strength lies in its cooperation with companies and with the rest of the world around it. Contacts with companies and society help to develop research and education that satisfy the demands that the world around makes on the university and its students. Luleå University of Technology conducts research in the Faculty of engineering and the Faculty of arts and social sciences. Research at the University has an annual turnover of EUR 70 million and comprises 70 research subjects in 6 research profiles and 6 development profiles. The research is characterized by multidisciplinary cooperation between the University's research departments and close interaction with trade and industry and society. Both major international and national companies and small enterprises in the region are involved in the University's research and development projects. The companies also cooperate in the University's research centers. Torsten Braun, Marc Brogle, Geert Heijenk, Evgeny Osipov

28293031 1501 - 1547 of 1547
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