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  • 901.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Android platform-based individual privacy information protection system2016Ingår i: Personal and Ubiquitous Computing, ISSN 1617-4909, E-ISSN 1617-4917, Vol. 20, nr 6, s. 875-884Artikel i tidskrift (Refereegranskat)
    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

  • 902.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Consensus of Networked Euler-Lagrange Systems under Time-Varying Sampled-Data Control2018Ingår i: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 14, nr 2, s. 535-544Artikel i tidskrift (Refereegranskat)
    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.

  • 903.
    Zhang, Yi-Qing
    et al.
    Department of Electronic Engineering, and the Center of Smart Networks and Systems, School of Information Science and Engineering, Adaptive Networks and Control Laboratory, Fudan University, Shanghai, China.
    Li, Xiang
    Department of Electronic Engineering, and the Center of Smart Networks and Systems, School of Information Science and Engineering, Adaptive Networks and Control Laboratory, Fudan University, Shanghai, China.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Spectral Analysis of Epidemic Thresholds of Temporal Networks2020Ingår i: IEEE Transactions on Cybernetics, ISSN 2168-2267, E-ISSN 2168-2275, Vol. 50, nr 5, s. 1965-1977Artikel i tidskrift (Refereegranskat)
    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.

  • 904.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Parallel Processing Systems for Big Data: A Survey2016Ingår i: Proceedings of the IEEE, ISSN 0018-9219, E-ISSN 1558-2256, Vol. 104, nr 11, s. 2114-2136Artikel i tidskrift (Refereegranskat)
    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.

  • 905.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Hanzo, Lajos
    University of Southampton, School of Electronics and Computer Science, University of Southanpton.
    Full-Duplex Wireless Communications: Challenges, Solutions, and Future Research Directions2016Ingår i: Proceedings of the IEEE, ISSN 0018-9219, E-ISSN 1558-2256, Vol. 104, nr 7, s. 1369-1409Artikel i tidskrift (Refereegranskat)
    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.

  • 906.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Hanzo, Lajos
    University of Southampton.
    Large-scale MIMO-based wireless backhaul in 5G networks2015Ingår i: IEEE wireless communications, ISSN 1536-1284, E-ISSN 1558-0687, Vol. 22, nr 5, s. 58-66Artikel i tidskrift (Refereegranskat)
    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.

  • 907.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Prediction of user app usage behavior from geo-spatial data2016Ingår i: GeoRich '16: Proceedings of the Third International ACM SIGMOD Workshop on Managing and Mining Enriched Geo-Spatial Data, New York: ACM Digital Library, 2016, s. 37-42, artikel-id 7Konferensbidrag (Refereegranskat)
    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

  • 908.
    Zhao, Yali
    et al.
    The University of Melbourne, Australia.
    Vasilakos, Athanasios V.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Bailey, James
    The University of Melbourne, Australia.
    Sinnott, Richard
    The University of Melbourne, Australia.
    Profit Optimization for Splitting and Sampling Based Resource Management in Big Data Analytics-as-a-Service Platforms in Cloud Computing Environments2019Ingår i: IEEE 15th International Conference on eScience: eScience 2019, IEEE, 2019, s. 156-167Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Exploring optimal big data analytics solutions to benefit various domains in decision making and problem solving becomes an ever-important research area. Big data Analytics-as-a-Service (AaaS) platforms offer online AaaS to various domains in a pay-as-you-go model. Big data analytics incurs expensive costs and takes lengthy processing times due to large-scale computing requirements. To tackle the cost and time challenges for big data analytics, we focus on proposing efficient and automatic resource management algorithms to maximize profits and minimize query times while guaranteeing Service Level Agreements (SLAs) on Quality of Service (QoS) requirements of queries. For query processing constrained by tight deadlines and limited budgets, our proposed algorithms enable data splitting and sampling based resource scheduling for parallel and approximate processing that significantly reduce data processing times and resource costs. We formulate the multi-objective resource scheduling problem to optimize profits for AaaS platforms while guaranteeing SLAs of queries with minimized response times. We design extensive experiments for algorithm performance evaluation, results show our proposed algorithms outperform state-of-the-art algorithms that maximize profits for AaaS platforms while improving admission rates and minimizing response times for queries. The scheduling algorithms support elastic and automatic large-scale resource configurations to minimize resource costs, and deliver timely, cost-effective, and reliable AaaS with SLA guarantees.

  • 909.
    Zhohov, Roman
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Minovski, Dimitar
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap. InfoVista Sweden.
    Johansson, Per
    InfoVista Sweden.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Real-time Performance Evaluation of LTE for IIoT2018Ingår i: Proceedings of the 43rd IEEE Conference on Local Computer Networks (LCN) / [ed] Soumaya Cherkaoui, Karl Andersson, Fadi Al-Turjman, IEEE, 2018, s. 623-631Konferensbidrag (Refereegranskat)
    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%.

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  • 910.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    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 Networking2016Ingår i: IEEE Journal on Selected Areas in Communications, ISSN 0733-8716, E-ISSN 1558-0008, Vol. 34, nr 5, s. 1713-1727Artikel i tidskrift (Refereegranskat)
    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.

  • 911.
    Zhou, Fanfu
    et al.
    hanghai Key Laboratory of Scalable Computing and Systems, Shanghai Jiao Tong University, Shanghai 200240, China.
    Qi, Zhengwei
    hanghai Key Laboratory of Scalable Computing and Systems, Shanghai Jiao Tong University, Shanghai 200240, China.
    Yao, Jianguo
    hanghai Key Laboratory of Scalable Computing and Systems, Shanghai Jiao Tong University, Shanghai 200240, China.
    Ma, Ruhui
    hanghai Key Laboratory of Scalable Computing and Systems, Shanghai Jiao Tong University, Shanghai 200240, China.
    Wang, Bing
    igh Performance and Distributed Computing, Queen’s University, Belfast BT7 1NN, United Kingdom.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Guan, Haibing
    hanghai Key Laboratory of Scalable Computing and Systems, Shanghai Jiao Tong University, Shanghai 200240, China.
    D2 FL: Design and Implementation of Distributed Dynamic Fault Localization2018Ingår i: IEEE Transactions on Dependable and Secure Computing, ISSN 1545-5971, E-ISSN 1941-0018, Vol. 15, nr 3, s. 378-392Artikel i tidskrift (Refereegranskat)
    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. 

  • 912.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Machine Learning on Big Data: Opportunities and Challenges2017Ingår i: Neurocomputing, ISSN 0925-2312, E-ISSN 1872-8286, Vol. 237, s. 350-361Artikel i tidskrift (Refereegranskat)
    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.

  • 913.
    Zhu, Nanhao
    et al.
    CETC Group, GCI Science and Technology Co.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A generic framework for energy evaluation on wireless sensor networks2016Ingår i: Wireless networks, ISSN 1022-0038, E-ISSN 1572-8196, Vol. 22, nr 4, s. 1199-1220Artikel i tidskrift (Refereegranskat)
    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

  • 914.
    Zhu, Nanhao
    et al.
    CETC Group, GCI Science and Technology Co.
    Vasilakos, Athanasios
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    EMrise: An Energy Management Platform for WSNs/WBANs2016Ingår i: Energy Management in Wireless Cellular and Ad-hoc Networks, Encyclopedia of Global Archaeology/Springer Verlag, 2016, s. 367-395Kapitel i bok, del av antologi (Refereegranskat)
    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.

  • 915.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A distributed approximation for multi-hop clustering problem in wireless sensor networks2016Ingår i: 2015 IEEE Global Communications Conference (GLOBECOM): San Diego, CA, 6-10 Dec 2015, Piscataway, NJ: IEEE Communications Society, 2016, artikel-id 7416941Konferensbidrag (Refereegranskat)
    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

  • 916.
    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 tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Duplexer design and implementation for self-interference cancellation in full-duplex communications2016Ingår i: European Signal Processing Conference, EUSIPCO 2016, Piscataway, NJ: IEEE Computer Society Digital Library, 2016, s. 125-129, artikel-id 7760223Konferensbidrag (Refereegranskat)
    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

  • 917.
    Zisad, Sharif Noor
    et al.
    Department of Computer Science and Engineering, University of Chittagong, Chittagong, Bangladesh.
    Chowdhury, Etu
    University of Chittagong, Chittagong 4331, Bangladesh.
    Hossain, Mohammad Shahadat
    University of Chittagong, Bangladesh.
    Islam, Raihan Ul
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    An Integrated Deep Learning and Belief Rule-Based Expert System for Visual Sentiment Analysis under Uncertainty2021Ingår i: Algorithms, E-ISSN 1999-4893, Vol. 14, nr 7, artikel-id 213Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Visual sentiment analysis has become more popular than textual ones in various domains for decision-making purposes. On account of this, we develop a visual sentiment analysis system, which can classify image expression. The system classifies images by taking into account six different expressions such as anger, joy, love, surprise, fear, and sadness. In our study, we propose an expert system by integrating a Deep Learning method with a Belief Rule Base (known as the BRBDL approach) to assess an image’s overall sentiment under uncertainty. This BRB-DL approach includes both the data-driven and knowledge-driven techniques to determine the overall sentiment. Our integrated expert system outperforms the state-of-the-art methods of visual sentiment analysis with promising results. The integrated system can classify images with 86% accuracy. The system can be beneficial to understand the emotional tendency and psychological state of an individual.

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  • 918.
    Zisad, Sharif Noor
    et al.
    Department of Computer Science and Engineering, University of Chittagong, Chittagong, Bangladesh.
    Hossain, Mohammad Shahadat
    Department of Computer Science and Engineering, University of Chittagong, Chittagong, Bangladesh.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Speech emotion recognition in neurological disorders using Convolutional Neural Network2020Ingår i: Proceedings of the 13th International Conference on Brain Informatics (BI2020), Springer, 2020, s. 287-296Konferensbidrag (Refereegranskat)
    Abstract [en]

    Detecting emotions from the speech is one of the emergent research fields in the area of human information processing. Expressing emotion is a very diffcult task for a person with neurological disorder. Hence, a Speech Emotion Recognition (SER) system may solve this by ensuring a barrierless communication. Various research has been carried out in the area of SER. Therefore, the main objective of this research is to develop a system that can recognize emotion from the speech of a neurologically disordered person. Since convolutional neural network (CNN) is an effective method, it has been considered to develop the system. The system uses tonal properties like MFCCs. RAVDESS audio speech and song databases for training and testing. In addition, a custom local dataset developed to support further training and testing. The performance of the proposed system compared with the traditional machine learning models as well as with the pre-trained CNN models including VGG16 and VGG19. The results demonstrate that the CNN model proposed in this research performed better than the mentioned machine learning techniques. This system enables one to classify eight emotions of neurologically disordered person including calm, angry, fearful, disgust, happy, surprise, neutral and sad.

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  • 919.
    Åhlund, Andreas
    et al.
    Umeå University, Department of Computer Science.
    Mitra, Karan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Johansson, Dan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Åhlund, Christer
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zaslavsky, Arkady
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Context-aware application mobility support in pervasive computing environments2009Ingår i: Proceedings of the 6th International Conference on Mobile Technology, Application & Systems : 2009, Nice, France, September 02 - 04, 2009, New York: ACM Digital Library, 2009Konferensbidrag (Refereegranskat)
    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.

  • 920.
    Åhlund, Christer
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Extended mobile IP and support for global connectivity in hybrid networks2005Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    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.

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  • 921.
    Åhlund, Christer
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Supporting global connectivity in heterogeneous IP networks2002Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    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.

  • 922.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Brännström, Robert
    Andersson, Karl
    Tjernström, Örjan
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Multimedia flow mobility in heterogeneous networks using multihomed mobile IPv62006Ingår i: Proceedings of the 4th International Conference on Advances in Mobile Computing and Multimedia: MoMM 2006, 2006Konferensbidrag (Refereegranskat)
    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.

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  • 923.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Brännström, Robert
    Andersson, Karl
    Tjernström, Örjan
    Port-based multihomed mobile IPv6 for heterogeneous networks2006Ingår i: 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, s. 567-568Konferensbidrag (Refereegranskat)
    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.

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  • 924.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Brännström, Robert
    Zaslavsky, Arkady
    A multihoming approach to mobile IP2003Ingår i: Swedish National Computer Networking Workshop - Proceedings: SNCNW 2003, Stockholm, 2003Konferensbidrag (Övrigt vetenskapligt)
    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.

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  • 925.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Brännström, Robert
    Zaslavsky, Arkady
    Agent selection strategies in wireless networks with multihomed mobile ip2004Ingår i: 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, s. 197-206Konferensbidrag (Refereegranskat)
    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.

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  • 926.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Brännström, Robert
    Zaslavsky, Arkady
    M-mip: extended mobile ip to maintain multiple connections to overlapping wireless access networks2005Ingår i: 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, s. 204-213Konferensbidrag (Refereegranskat)
    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.

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  • 927.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Brännström, Robert
    Zaslavsky, Arkady
    Running variance metric for evaluating performance of wireless ip networks in the mobilecity testbed2005Ingår i: 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, s. 120-127Konferensbidrag (Refereegranskat)
    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.

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  • 928.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Brännström, Robert
    Zaslavsky, Arkady
    Traffic load metrics for multihomed mobile IP and global connectivity2006Ingår i: Telecommunications Systems, ISSN 1018-4864, E-ISSN 1572-9451, Vol. 33, nr 1-3, s. 155-185Artikel i tidskrift (Refereegranskat)
    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.

  • 929.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Börjesson, Mikael
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Pettersson, Jan
    Brännström, Robert
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Larsson, Roger
    Johansson, Dan
    Granlund, Daniel
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Andersson, Karl
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Project: Sense Smart City2010Övrigt (Övrig (populärvetenskap, debatt, mm))
    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.

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  • 930.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Toffia, Mario
    Luleå tekniska universitet.
    Elf, Stefan
    Luleå tekniska universitet.
    Nordmark, Håkan
    Luleå tekniska universitet.
    A framework for adaptive applications2000Konferensbidrag (Övrigt vetenskapligt)
    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.

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  • 931.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Wallin, Stefan
    Andersson, Karl
    Brännström, Robert
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    A service level model and Internet mobility monitor2008Ingår i: Telecommunications Systems, ISSN 1018-4864, E-ISSN 1572-9451, Vol. 37, nr 1-3, s. 49-70Artikel i tidskrift (Refereegranskat)
    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.

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  • 932.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zaslavsky, Arkady
    Extending global IP connectivity for ad hoc networks2003Ingår i: Telecommunications Systems, ISSN 1018-4864, E-ISSN 1572-9451, Vol. 24, nr 2-4, s. 221-250Artikel i tidskrift (Refereegranskat)
    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.

  • 933.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zaslavsky, Arkady
    Integration of ad hoc network and IP network capabilities for mobile hosts2003Ingår i: 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, s. 482-489Konferensbidrag (Refereegranskat)
    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.

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  • 934.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zaslavsky, Arkady
    "Mobile city" ad hoc wireless network support for regional communities2001Ingår i: Proceedings: The Path to 4G Mobile, 2001Konferensbidrag (Refereegranskat)
  • 935.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zaslavsky, Arkady
    Multihoming with mobile IP2003Ingår i: 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, s. 235-243Konferensbidrag (Refereegranskat)
    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.

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  • 936.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zaslavsky, Arkady
    Software solutions to Internet connectivity in mobile ad hoc networks2002Ingår i: Product focused software process improvement: 4th international conference ; proceedings / [ed] Markku Oivo, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2002, s. 559-571Konferensbidrag (Refereegranskat)
    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.

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  • 937.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zaslavsky, Arkady
    Support for wireless connectivity in hot spot areas2002Ingår i: MOST: Technology for Mobile Society: MOST International Conference. Proceedings / [ed] Mieczysław R Muraszkiewicz, Warsaw: Most Press , 2002Konferensbidrag (Refereegranskat)
  • 938.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zaslavsky, Arkady
    Wireless network support for connectivity in regional communities2001Ingår i: 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), 2001Konferensbidrag (Refereegranskat)
  • 939.
    Åhlund, Christer
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik, Datavetenskap.
    Zaslavsky, Arkady
    Matskin, M.
    Supporting mobile business applications in hot spot areas with pervasive infrastructure2002Ingår i: M-business 2002: evolution sceniarios for emerging mobile commerce services ; the 1st International Conference on Mobile Business ; 8 - 9 July 2002, Athens, Greece, Athens, 2002Konferensbidrag (Refereegranskat)
  • 940.
    Åhlén, Mikael
    et al.
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Winbjörk, Martin
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Hietala, Simon
    Luleå tekniska universitet, Institutionen för system- och rymdteknik.
    Conquest - outdoor based games enhanced with sensors2014Ingår i: Lecture Notes in Computer Science, ISSN 0302-9743, E-ISSN 1611-3349, Vol. 8867, s. 68-71Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents Conquest, a game platform in the class of trans-reality games in pervasive gaming that combines old classical outdoor games that have been introduced in computer games with the possibilities of today’s technology to enhance outdoor based games. The proposed platform use Near Field Communication (NFC), locationawareness with Global Positioning System (GPS) and mobile communication to support three game types that are similar and share a common foundation in the context of sensors and user interaction. Finally, we present a prototype with the usage of the Actor model to efficiently map each physical CPU-powered device to a virtual actor in the back-end.

  • 941.
    Ödling, Ola
    et al.
    Erisoft AB, Sweden.
    Wallin, Stefan
    Erisoft AB, Sweden.
    Building MIB Applications1994Ingår i: IEEE Network Operations and Management Symposium: Symposium Record : Wednesday, February 16: Sessions 11 - 20, Piscataway, NJ: IEEE Communications Society, 1994, Vol. 2, s. 565-575Konferensbidrag (Refereegranskat)
    Ladda ner fulltext (pdf)
    fulltext
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