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  • 601.
    Gunasekera, Kutila
    et al.
    Monash University, Melbourne, VIC.
    Krishnaswamy, Shonali
    Monash University, Melbourne, VIC.
    Loke, Seng Wai
    La Trobe University.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Runtime efficiency of adaptive mobile software agents in pervasive computing environments2009In: AUPC '09: ICPS 2009 & co-located workshops compilation proceedings, July 13-16, 2009, Imperial College, London, UK, New York: ACM Digital Library, 2009, p. 123-131Conference paper (Refereed)
    Abstract [en]

    Developing software that can support heterogeneous hardware platforms, adapt to dynamic highly variable environments and meet rapidly changing requirements is a challenge of pervasive computing. Dynamic adaptive software agents are a promising approach to develop software for such environments. We previously proposed an agent architecture which brings together features such as runtime adaptivity, agent mobility, platform-independence, context-awareness and lightweightness which are desirable in pervasive environments. In this paper, we propose and analyse a cost model of network load for our runtime adaptive mobile software agents. We compare our adaptive agents against standard non-adaptive mobile agents using this cost model. Subsequent experimental results demonstrate that our agents outperform non-adaptive mobile agents. We also propose and discuss further features which make our adaptive agent based software solution more suitable for pervasive computing environments.

  • 602.
    Wallin, Stefan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. Data Ductus Nord AB, Skellefteå, Sweden.
    Leijon, Viktor
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Landén, Leif
    Data Ductus Nord AB, Skellefteå, Sweden.
    Statistical analysis and prioritisation of alarms in mobile networks2009In: International Journal of Business Intelligence and Data Mining, ISSN 1743-8195, Vol. 4, no 1, p. 4-21Article in journal (Refereed)
    Abstract [en]

    Telecom Service Providers are faced with an overwhelming flow of alarms, which makes good alarm classification and prioritization very important. This paper first provides statistical analysis of data collected from a real-world alarm flow and then presents a quantitative characterization of the alarm situation. Using data from the trouble ticketing system as a reference, we examine the relationship between mechanical classification of alarms and the human perception of them.Using this knowledge of alarm flow properties and trouble ticketing information, we suggest a neural network-based approach for alarm classification. Tests using live data show that our prototype assigns the same severity as a human expert in 50% of all cases, compared to 17% for a naive approach.

  • 603.
    Wallin, Stefan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Leijon, Viktor
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Telecom network and service management: an operator survey2009In: Wired-Wireless Multimedia Networks and Services Management: 12th IFIP/IEEE International Conference on Management of Multimedia and Mobile Networks and Services, MMNS 2009, Venice, Italy, October 26-27, 2009. Proceedings / [ed] Tom Pfeifer; Paolo Bellavista, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2009, p. 15-26Conference paper (Refereed)
    Abstract [en]

    It is hard to know which research problems in network management we should focus our attention on. To remedy this situation we have surveyed fifteen different telecom operators on four continents to gather some feedback on what they desire and expect from the network management research community. Their input forms a foundation for future directions in network management research, and provides us with valuable insight into what the most urgent problems are in industry.

  • 604.
    Andersson, Karl
    et al.
    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.
    A mobility management scheme for heterogeneous environments supporting vehicular speeds using a policy-based approach2008In: Proceedings of the 5th International Workshop Conference on Performance Modelling and Evaluation of Heterogeneous Networks: (HET-NETs), 2008Conference paper (Refereed)
    Abstract [en]

    Today, handsets and terminals are typically equipped with multiple radio interfaces. Meanwhile, various types of access networks using different radio technologies are being deployed all over the world. Also, there is a strong trend towards All-IP-Networks following the principle "Everything over IP", and "IP over everything". This development is leading researchers into the area of heterogeneous networking and overlay topologies.This paper focuses on mobility management issues related to such an environment supporting vehicular speeds of users using a policy-based approach and a network-layer metric for access network selection.A Mobile IP-based architecture is proposed where mobility bindings are sent periodically at a frequency depending on the speed of the user also taking variations in the network-layer metric into account and the overall signaling cost. The architecture is designed with a focus on minimizing packet losses and timely handling of vertical hand-overs.

  • 605.
    Andersson, Karl
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Elkotob, Muslim
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A new MIP-SIP interworking scheme2008In: MUM'08 Proceedings: 7th ACM International Conference on Mobile and Ubiquitous Multimedia, December 3 - 5, 2008, Umeå, Sweden, New York: ACM Digital Library, 2008, p. 117-120Conference paper (Refereed)
    Abstract [en]

    Mobility management is today handled at various layers in the network stack including the datalink layer, the network layer, the transport layer and the application layer. Also, cross-layer designed solutions exist and the most known example is the work performed by IEEE currently standardizing media-independent handover services under the name of IEEE 802.21.This paper proposes a new interworking scheme for Mobile IP and the Session Initiation Protocol being the most popular solutions for mobility management at the network and application layers respectively. The goal is to deliver seamless mobility for both TCP-based and UDP-based applications taking the best features from each mobility management scheme. In short, this paper proposes that TCP connections are handled through Mobile IP while UDP-based connection-less applications may use the Session Initiation Protocol for handling mobility. The two mobility management solutions are integrated into one common solution.

  • 606.
    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.

  • 607.
    Rahmani, Rahim
    et al.
    Mittuniversitetet, Sundsvall.
    Hjelm, Mats
    Mittuniversitetet, Sundsvall.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Active queue management for TCP friendly rate control traffic in heterogeneous networks2008In: International Conference on Telecommunications: ICT 2008, Piscataway, NJ: IEEE Communications Society, 2008, p. 1-7Conference paper (Refereed)
    Abstract [en]

    With the increasing number of media flows using UDP in IP networks there is a strong need to enable fairness between UDP and TCP traffic. The TCP traffic will suffer because of the unresponsiveness of UDP to congestion in the IP network. To enable responsiveness of UDP traffic, the TCP-Friendly Rate Control (TFRC) protocol can be used. With the coexistence of TCP and UDP, where the rate adaptation of UDP is managed by the TFRC protocol, knowledge is needed about how Active Queue Management (AQM) algorithms perform to optimize networks performance. This paper studies the behavior of several AQM algorithms when small packet UDP flows compete with TCP flows in a heterogeneous network. A simulation study is presented, showing the results of different AQM algorithms. It shows that the Adaptive AQM (AAQM) is very promising with respect to responsiveness and robustness.

  • 608.
    Hirche, Johannes
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Bomark, Peter
    Natural User Interface Europe AB.
    Bauer, Mikael
    Natural User Interface Europe AB.
    Solyga, Pawel
    Natural User Interface Europe AB.
    Adaptive interface for text input on large-scale interactive surfaces2008In: 2008 IEEE International Workshop on Horizontal Interactive Human-Computer System: Amsterdam, Netherlands, 1 - 3 October 2008, Piscataway, NJ: IEEE Communications Society, 2008, p. 163-166Conference paper (Refereed)
    Abstract [en]

    In this paper we present a novel approach to text input on large interactive surfaces using a combination of strategies to resolve the inherent difficulties with text input on such a device. Instead of using a conventional full size QWERTY based layout, the idea is to use a very limited set of buttons that, by using word prediction and hints, would only require minimal finger movement. The input mechanism is somewhat related to input methods employed when using keyboards with a limited size and amount of keys, commonly found in phones and other 10 digit keyboards. Given that the main motivation to this approach was not the limited size but rather to overcome the difficult task of locating keys with fingers on a flat and featureless surface, making touchtyping very difficult and requiring frequent visual monitoring of the finger position, we opted to enhance the interaction with easily made gestures, a layout that adapts to the hand anatomy of the user, and easy control over the text prediction.

  • 609. Elkotob, Muslim
    et al.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Analysis and measurement of session setup delay and jitter in VoWLAN using composite metrics2008In: MUM'08 Proceedings: 7th ACM International Conference on Mobile and Ubiquitous Multimedia, December 3 - 5, 2008, Umeå, Sweden / [ed] Arkady Zaslavsky, New York: ACM Digital Library, 2008, p. 190-197Conference paper (Refereed)
    Abstract [en]

    In this paper we look at the signaling for session mobility using the Session Initiation Protocol (SIP) and the Session Description Protocol (SDP). Bearing in mind that perceived voice quality is sensitive mostly to delay variation (also called jitter), we work on bounding that value for providing a better voice Quality of Service over Wireless LAN (WLAN). For mobility we use a hybrid SIP-MIP stack. The basic idea is to combine the strengths of MIP for doing fast handovers and the strengths of SIP for powerful session adaptation capabilities. Numerical calculation figures as well as real implementation results are provided. It can be observed that the session update cycle during mobility can be modified in such a way that session delay variation bounds achieved are quite low and there are almost no spikes. We use composite performance metrics that we defined in previous work to analyze the correlation between the data patterns for session signaling delay in the classical case and our proposed case to better highlight the achieved performance delta.

  • 610.
    Nugent, Chris
    et al.
    University of Ulster.
    Hong, Xin
    University of Ulster.
    Hallberg, Josef
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Finlay, Dewar
    University of Ulster.
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Assessing the impact of individual sensor reliability within smart living environments2008In: IEEE International Conference onAutomation Science and Engineering: CASE 2008, Piscataway, NJ: IEEE Communications Society, 2008, p. 685-690Conference paper (Refereed)
    Abstract [en]

    The potential of smart living environments to provide a form of independent living for the ageing population is becoming more recognised. These environments are comprised of sensors which are used to assess the state of the environment, some form of information management to process the sensor data and finally a suite of actuators which can be used to change the state of the environment. When providing a form of support which may impinge upon the well being of the end user it is essential that a high degree of reliability can be maintained. Within this paper we present an information management framework to process sensor based data within smart environments. Based on this framework we assess the impact of sensor reliability on the classification of activities of daily living. From this assessment we show how it is possible to identify which sensors within a given set of experiments can be considered to be the most critical and as such consider how this information may be used to propose a set of guidelines which may be adopted for managing sensor reliability from a practical point of view.

  • 611.
    Elkotob, Muslim
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Autonomic resource management in IEEE 802.11 open access networks2008Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This work is inspired by the autonomic networking paradigm. It investigates the issue of making network resource management mechanisms in the access part of wireless networks self-aware and self-configuring. Open access networks (OAN) have private WLAN cells made available for public use and enable bypassing mobile users to profit from continuous coverage, allowing private and public subscribers to share a common infrastructure. Resources are network parameters, e.g. bandwidth, capacity, that have to be fairly and accurately allocated, distributed, and managed in order to optimize performance and ensure proper and fair operation. Analyzing and exploring existing multimedia session and resource management mechanisms on the wireless part is a crucial step for determining their limitations and shortcomings. A new way of making OANs self-aware is proposed and a self-configuring mechanism which has a competitive advantage in the qualitative sense over already existing mechanisms is designed and developed. The amount of network resources as well as the timing and form of their availability are decisive for enabling service functionality and providing a sufficient quality of service level. Our area of discourse is the "last- mile" part of an 802.11 network; i.e. the part between the access point and the mobile node. In OANs, maintaining and updating rates for different flows used by a single terminal traversing many adjacent APs is a challenge in itself. It is solved by using several key design factors. Monitoring the environment locally and updating the designed information structures leads to network self-awareness. Next, a high-level mechanism that aggregates information from several protocols including CARD (Candidate Access Router Discovery), MIP (Mobile IP), and SIP (Session Initiation Protocol) is defined. It specifies the interactions between the mobile terminal and the access point controller. Then capacity maintenance and rate allocation issues at the two end-points of the last-mile are analyzed. The overhead in OANs required for the launching or reconfiguration of a real-time session can be significantly reduced by a proposed algorithm which performs parameter injection into a multimedia data stream instead of following the classical negotiation path. A solution to change the session characteristics of an application that adapts to varying network conditions was developed, including a QoS solution with SIP and MIP to optimize the session characteristics by taking into account the changed conditions in the network. With this approach, reduced session signaling delay and low jitter values are achieved as implementation results show. The thesis is concluded by considering the general issues: self-aware node architectures, self-configuring resource management.

  • 612.
    Jayaraman, Prem Prakash
    et al.
    Monash University, Melbourne, VIC.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Delsing, Jerker
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Cost efficient data collection of sensory originated data using context-aware mobile devices2008In: 2008 Ninth International Conference on Mobile Data Management workshops: MDMW ; Beijing, China, 27 - 30 April 2008, Piscataway, NJ: IEEE Communications Society, 2008, p. 190-197Conference paper (Refereed)
    Abstract [en]

    Sensory originated data collection and processing has always been a big challenge in wireless sensor networks (WSN). WSN represent a distributed producer of large amount of valuable data required by varied number of applications. In this paper we propose the use of context aware data mules (CADAMULE) as a solution for smart data collection within sensor networks. We present an extension to Context Spaces modelling theory by incorporating context discovery at runtime. This facilitates our system to discover new context attributes by looking into previous situations and events when pre-defined context is not sufficient for the reasoning process. We use this model as a base to provide contextual information to the mobile data mule whose spare capacity for communication and processing can be used to collect and process sensor data. The focus of the paper is to propose and evaluate a cost-efficient data collection technique which uses a cost formula computed from the context information obtained by the system. We validate our system by a simulation in which we try to reason out and identify the best and also the most cost efficient data mule. The context aware data mule negotiates with the sensor node collecting and delivering the data to the sink

  • 613.
    Jayaraman, Prem Prakash
    et al.
    Monash University, Melbourne, VIC.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Delsing, Jerker
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Coverage area computation on the run for efficient sensor data collection2008In: New technologies, mobility and security: proceedings of NTMS '2008 conference and workshops ; [held in Tangier, Morocco during November 5 - November 7 2008] / [ed] Akshai Aggarwal, Piscataway, NJ: IEEE Communications Society, 2008Conference paper (Refereed)
    Abstract [en]

    Wireless sensor networks have emerged as a key area of research in recent years. With the dominance of ubiquitous and pervasive era of computing, these networks present a rich infrastructure for valuable information. In this paper we focus on efficient data collection in sensor networks by proposing an algorithm to compute a coverage (collection) area using smart mobile objects. The algorithm proposed computes a collection area dynamically covering nodes around the mobile objects current location. It uses a weighed graph technique to identify nodes from which data can be collected efficiently by the mobile object discarding the rest. The proposed algorithm computes the collection area using Voronoi Diagrams and Delaunay triangle. We validate the proposed algorithm by simulating the algorithm over a Bluetooth based sensor network. We also evaluate the algorithms efficiency to compute the coverage area by changing the mobile objects context parameters.

  • 614.
    Winkler, F.
    et al.
    NEC Europe Ltd..
    Abbadessa, D.
    NEC Europe Ltd..
    Silva, J. Da
    NEC Europe Ltd..
    Girao, J.
    NEC Europe Ltd..
    Schmidt, Mischa
    NEC Laboratories Europe, NEC Europe Ltd., Heidelberg.
    Enriching IPTV Services and Infrastructure with Identity Management2008In: IEEE GLOBECOM 2008, Global Telecommunications Conference: New Orleans, Nov. 30 2008-Dec. 4 2008, Piscataway, NJ: IEEE Communications Society, 2008Chapter in book (Refereed)
    Abstract [en]

    IPTV is regarded as one of the key technologies of triple play services by telecommunication incumbents. It is seen as the differentiator to reduce customer churn. However, as more operators deploy this service, the factors for differentiation are dissolving rapidly. In this paper we present how identity management can enrich IPTV and thus provide a variety of new business opportunities that will foster an operator's position and the contractual bindings with its customers. We present novel business models that are made possible by integrated identity management and describe their importance to the user. Furthermore, we address privacy aspects for IPTV service portfolios - a topic which is crucial to gain user acceptance for new services.

  • 615.
    Granlund, Daniel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Brännström, Robert
    Estimating network performance using low impact probing2008In: Proceedings of the 1st Workshop on Wireless Broadband Access for Communities and Rural Developing Regions: WIRELESS4D '08 / [ed] Andreas J. Kassler, 2008Conference paper (Refereed)
    Abstract [en]

    This paper focuses on estimating network performance in order to make proper decisions regarding data flow path selection. The purpose is to estimate the available bandwidth without flooding the network with traffic like traditional bandwidth measurement tools such as Iperf. By using small datagrams to probe the network rather than flooding the link, delay and jitter can be measured and used for calculations. The idea is to use statistical information about the delay to make an acceptable estimation of the available bandwidth. Lntransform of delay and standard deviation of delay were found to be the most accurate parameters and provide the best correlation. Also, some network technologies have a significant difference in up and downlink delay. This can pose a problem when estimating the link performance. Therefore this paper also proposes a solution to handle measurements in asymmetrical links.

  • 616.
    Andersson, Karl
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Lundahl, Carl-Gustav
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Lundmark, Martin
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Science.
    Nordvik, Enar
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Pantze, Anna
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Förslag till handlingsplan för utveckling av LTU Skellefteå: Att synas med stolthet2008Report (Other academic)
  • 617.
    Winkler, Florian
    et al.
    NEC Europe Ltd..
    Schmidt, Mischa
    NEC Europe Ltd..
    Felis, Sebastian
    NEC Europe Ltd..
    Neuwirt, Oleg
    NEC Europe Ltd..
    Silva, Joao
    NEC Europe Ltd..
    Richter, Nils
    NEC Europe Ltd..
    Abbadessa, Danile
    NEC Europe Ltd..
    Identity management for IMS-based IPTV2008In: 2008 IEEE Global Telecommunications Conference: New Orleans, Louisiana, 30 November 2008-04 December 2008., Piscataway, NJ: IEEE Communications Society, 2008, p. 1637-1641Conference paper (Refereed)
    Abstract [en]

    IPTV as an integral part of triple play service offers is regarded as a major differentiation factor by incumbent telecommunication operators. However, as more operators provide these services, differentiation is fading. Analysts agree that the key to differentiation are value added services which in the long term require business collaborations of incumbents and 3rd party Service Providers. Additional value is added by integrating existing and well known Internet services into those service portfolios.In this paper, we present how Identity Management technology can simplify the setup of these collaborations and enhance the user experience by secure, anonymous and seamless service usage, e.g. by providing Single Sign On and pseudonyms. We furthermore detail an architecture that combines IPTV based on the IPMultimedia Subsystem with Identity Management to offer consumers a comfortable, privacy aware access to value added services. Especially in the context of IPTV, these are important attributes to reach a high and sustainable user acceptance.

  • 618.
    Andersson, Karl
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Gukhool, Balkrishna Sharma
    Electrical and Computer Engineering Department, Sherbrooke University.
    Cherkaoui, Soumaya
    Electrical and Computer Engineering Department, Sherbrooke University.
    Mobility management for highly mobile users and vehicular networks in heterogeneous environments2008In: 2008 IEEE 33rd Conference on Local Computer Networks: [LCN 2008] ; Montreal, AB, Canada, 14 - 17 October 2008, Piscataway, NJ: IEEE Communications Society, 2008, p. 593-599Conference paper (Refereed)
    Abstract [en]

    With the recent developments in wireless networks, different radio access technologies are used in different places depending on capacity in terms of throughput, cell size, scalability etc. In this context, mobile users, and in particular highly mobile users and vehicular networks, will see an increasing number and variety of wireless access points enabling Internet connectivity. Such a heterogeneous networking environment needs, however, an efficient mobility management scheme offering the best connection continuously. In this paper, a mobility management architecture focusing on efficient network selection and timely handling of vertical and horizontal hand-overs is proposed. The solution is based on Mobile IP where hand-over decisions are taken based upon calculations of a metric combining delay and delay jitter. For efficiency reasons, the frequency of binding updates is dynamically controlled, depending on speed and variations in the metric. The dynamic frequency of binding updates helps the timely discovery of congested access points and cell edges so as to allow efficient hand-overs that minimize packet drops and hand-over delays.Results show that the overall signaling cost is decreased and changes in networking conditions are detected earlier compared to standard Mobile IP.

  • 619.
    Padovitz, A.
    et al.
    Centre for Distributed Systems and Software Engineering, Monash University.
    Loke, Seng Wai
    Department of Computer Science and Computer Engineering, La Trobe University.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Multiple-agent perspectives in reasoning about situations for context-aware pervasive computing systems2008In: IEEE transactions on systems, man and cybernetics. Part A. Systems and humans, ISSN 1083-4427, E-ISSN 1558-2426, Vol. 38, no 4, p. 729-742Article in journal (Refereed)
    Abstract [en]

    In open heterogeneous context-aware pervasive computing systems, suitable context models and reasoning approaches are necessary to enable collaboration and distributed reasoning among agents. This paper proposes, develops, and demonstrates the following: 1) a novel context model and reasoning approach developed with concepts from the state-space model, which describes context and situations as geometrical structures in a multidimensional space; and 2) a context algebra based on the model, which enables distributed reasoning by merging and partitioning context models that represent different perspectives of computing entities over the object of reasoning. We show how merging and reconciling different points of view over context enhances the outcomes of reasoning about the context. We develop and evaluate our proposed algebraic operators and reasoning approaches with cases using real sensors and with simulations. We embed agents and mobile agents with these modeling and reasoning capabilities, thus facilitating context-aware and adaptive mobile agents operating in open pervasive environments.

  • 620.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    On access network selection models in heterogeneous networking environments2008Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis proposes and evaluates architectures and algorithms for access network selection in heterogeneous networking environments. The ultimate goal is to select the best access network at any time taking a number of constraints into account including user requirements and network characteristics. The proposed architecture enables global roaming between access networks within an operator's domain, as well as across operators without any changes in the data and control plane of the access networks being required. Also, the proposed architecture includes an algorithm for measuring performance of access networks that can be used on a number of access technologies being wired or wireless. The proposed access network selection algorithm also has an end-to-end perspective giving a network performance indication of user traffic being communicated. The contributions of this thesis include an implementation of a simulation model in OPNET Modeler, a proposal of a metric at the network layer for heterogeneous access networks, an implementation of a real-world prototype, a study of multimedia applications on perceived quality of service, an access network selection algorithm for highly mobile users and vehicular networks, and an extension of the mentioned access network selection algorithm to support cross-layer decision making taking application layer and datalink layer metrics into account.

  • 621.
    Wiberg, M.
    et al.
    Umeå university.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Preface2008In: MUM'08 Proceedings: 7th ACM International Conference on Mobile and Ubiquitous Multimedia, December 3 - 5, 2008, Umeå, Sweden, ACM Digital Library, 2008, p. vii-viiiConference paper (Other academic)
  • 622. Granlund, Daniel
    et al.
    Gylling, Arne
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Osipov, Evgeny
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brännström, Robert
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Jacquier, Anna
    Elkotob, Muslim
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    Åhl, Anneli
    Project: BASICNET2008Other (Other (popular science, discussion, etc.))
    Abstract [en]

    Broadband Access Services In Converging NETworks

  • 623.
    Leijon, Viktor
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Wallin, Stefan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Ehnmark, Johan
    Data Ductus.
    SALmon: a Service Modeling Language and Monitoring Engine2008In: IEEE International Symposium on Service-Oriented System Engineering: SOSE '08 / [ed] Jonathan Lee; Deron Liang; Y.C. Cheng, Los Alamitos, Calif: IEEE Communications Society, 2008, p. 202-207Conference paper (Refereed)
    Abstract [en]

    To be able to monitor complex services and examine their properties we need a modeling language that can express them in an efficient manner. As telecom operators deploy and sell increasingly complex services the need to monitor these services increases. We propose a novel domain specific language called SALmon, which allows for efficient representation of service models, together with a computational engine for evaluation of service models. This working prototype allows us to perform  experiments with full scale service models, and proves to be a good trade-off between simplicity and expressive power.

  • 624.
    Albayrak, Sahin
    et al.
    DAI-Labor, Technische Universität Berlin, Germany.
    Elkotob, Muslim
    DAI-Labor, Technische Universität Berlin, Germany.
    Toker, Ahmet
    DAI-Labor, Technische Universität Berlin, Germany.
    Smart middleware for mutual service-network awareness in evolving 3GPP networks: network aware applications & application aware networks2008In: 2008 3rd International Conference on Communication System Software and Middleware and workshops: [COMSWARE 2008]; Bangalore, India, 6 - 10 January 2008, Piscataway, NJ: IEEE Communications Society, 2008, p. 44-50Conference paper (Refereed)
    Abstract [en]

    We have designed a smart middleware and are working on implementing and deploying it as a landmark architectural piece run by nodes of the Future Internet. The middleware we propose aims as a main goal at making applications and services fully network-aware in the sense that they utilize network resources and tune their own demands based on what the underlying networks can offer. On the other hand, the smart middleware makes networks service aware in the sense that networks also adapt their configuration to service demands. Challenges of the Future Internet such as scalability, increased interoperability, and smart collaboration between engines are addressed by our middleware. Focusing on 3GPP networks including IP Multimedia Subsystem (IMS) networks, this paper presents the architectural design of our middleware and shows in two showcases how and why it is capable of addressing future challenges. Scenarios such as service and network-aware coordinated load balancing and "always-best-connected" as a service verify the merits of our smart middleware design.

  • 625.
    Jayaraman, Prem Prakash
    et al.
    Caulfield School of Information Technology, Monash University.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Delsing, Jerker
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Smart sensing and sensor data collection on the move for modelling intelligent environments2008In: Next Generation Teletraffic and Wired/Wireless Advanced Networking: 8th International Conference, NEW2AN and 1st Russian Conference on Smart Spaces, ruSMART 2008, St. Petersburg, Russia, September 3-5, 2008. Proceedings / [ed] Sergey Balandin; Dimitri Moltchanov; Yevgeni Koucheryavy, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2008, p. 306-317Conference paper (Refereed)
    Abstract [en]

    With advent of pervasive computing and considerable acceptance of sensor networks, smart sensing techniques and data collection have been topics of interest. This paper presents a smart sensing and data collection technique from sensor networks using context aware high powered mobile objects within the environment. The paper proposes CAM-R a context aware robot that can move within smart environments sensing new sensor sources and collecting sensory originated data efficiently. Based on these sensed data sources, we propose an extension to context spaces model that builds a virtual model of the intelligent environment. This intelligent environment model built using extended context spaces can be used by number of context aware applications to efficiently query and retrieve data from the sensor network using CAM-R based data collection approach. We also present a prototype implementation of CAM-R built using off-the-shelf hardware and a context based cost function used to compute data collection decisions. We validate our system by implementing the virtual modelling of the intelligent environment based on simulated input obtained from CAM-R and sensors. We also evaluate CAM-Rby simulating and comparing the energy spent by the sensor nodes during data collection process using our proposed approach and traditional fixed sink based approach.

  • 626.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Smartness of pervasive computing systems through context-awareness2008In: Next Generation Teletraffic and Wired/Wireless Advanced Networking: 8th International Conference, NEW2AN and 1st Russian Conference on Smart Spaces, ruSMART 2008 St. Petersburg, Russia, September 3-5, 2008. Proceedings / [ed] Sergey Balandin; Dimitri Moltchanov; Yevgeni Koucheryavy, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2008, p. 261-262Conference paper (Refereed)
    Abstract [en]

    Emerging pervasive computing and communications technologies evolved into ample pioneering initiatives, leading towards a world in which computing systems are distributed, mobile, intelligent, supportive, unobtrusive, invisible and cooperative. Central to the notion of a pervasive systems is context-awareness. Context-aware computing endeavours to make systems aware of specific, relevant circumstances in the computing environment, and enable them to adapt their behaviour accordingly. Context-aware systems can process (intelligently) the context information acquired by any type of a sensor (either physical, computational or virtual). This, in turn, enhances services provided to users (including service personalization), makes pervasive systems smart by reacting (and possibly pro-acting) to changing circumstances, and enables adaptability and autonomy of systems, freeing users from avoidable sometimes routine interactions.

  • 627.
    Andersson, Karl
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Lövf, Eva
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Wood Science and Engineering.
    Studenters upplevelser av distansundervisning: en fallstudie2008Report (Other academic)
    Abstract [sv]

    Artikeln presenterar resultat från en studie av studenters upplevelser vid införande av modern videokonferensteknik i undervisningen. Studien omfattar 40 studenter vid fyra kurser. Resultaten indikerar att universitet och högskolor, förutom kostnadsbesparingar, lätt kan engagera specialistkompetens i kurser, erbjuda undervisning utanför campus och underlätta studentens självstudier. I sin bästa form uppnås både rums- och tidsoberoende. Samtidigt indikerar resultaten att det finns utrymme för förbättringar vid undervisning via videokonferenssändningar, främst i interaktionen mellan student och lärare. Oavsett lärarens pedagogik, ämnets inriktning och studenternas vana vid modern teknik så föredrog 39 av de 40 studenterna i undersökningen att ha en lärare på plats. Till viss del kan detta förklaras av teknikproblem, som delvis åtgärdats under kursernas genomförande, men även av att lärarna inte anpassat sin pedagogik fullt ut. Vår bedömning är att om rätt pedagogik används kan både kommunikation och interaktion fungera mycket bra och vara en utmärkt undervisningsform även om lärare och student inte befinner sig på samma plats.Vi föreslår att lärarna som sänder föreläsningarna ges tillfälle att interagera mer med studenterna, både synkront och asynkront, vilket kräver att kurserna planeras på annat sätt än vid traditionell campus-undervisning. Vidare föreslår vi att studenter på annan ort regelbundet erbjuds separata tillfällen för att diskutera och ställa frågor till läraren och gärna träffas fysiskt. Avslutningsvis föreslår vi att en särskild ämneskunnig producent, s.k. e-moderator, engageras parallellt med lärarens undervisning, för att stöda studenterna som följer föreläsningarna genom att besvara deras frågor. Alternativt kan en e-moderator uppmärksamma läraren på relevanta frågor som dyker upp, så att en utökad interaktion uppnås.

  • 628. Burstein, F.
    et al.
    Cowie, J.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Pedro, J. San
    Support for real-time decision making in mobile financial applications2008In: Handbook on Decision Support Systems 2: Variations, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2008, p. 81-106Chapter in book (Other academic)
  • 629.
    Burstein, Frada
    et al.
    Monash University, Melbourne, VIC.
    Cowie, Julie
    Department of Computing Science and Mathematics, University of Stirling.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Pedro, Jocelyn San
    Group Market Risk, National Australia Bank Limited, Melbourne.
    Support for real-time decision making in mobile financial applications2008In: Information Systems and E-Business Management, ISSN 1617-9846, E-ISSN 1617-9854, Vol. 6, no 3, p. 257-278Article in journal (Refereed)
    Abstract [en]

    Mobile users making real-time decisions based on current information need confidence that their context has been taken into consideration in producing the system's recommendations. This chapter reviews current use of mobile technologies for context-aware real-time decision support. Specifically, it describes a framework for assessing the impact of mobility in decision making. The framework uses dynamic context model of data quality to represent uncertainties in the mobile decision-making environment. This framework can be used for developing visual interactive displays for communicating to the user relevant changes in data quality when working in mobile environments. As an illustration, this chapter proposes a real-time decision support procedure for on-the-spot assistance to the mobile consumer when choosing the best payment option to efficiently manage their budget. The proposed procedure is based on multi-attribute decision analysis, scenario reasoning, and a quality of data framework. The feasibility of the approach is demonstrated with a mobile decision-support system prototype implementation.

  • 630.
    Kodikara, Ruwini
    et al.
    Centre for Distributed Systems and Software Engineering, Monash University.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Zaslavsky, Arkady
    Supporting adaptive real-time mobile communication with multilayer context awareness2008In: Wireless and Mobile Networking: IFIP Joint Conference on Mobile and Wireless Communications Networks (MWCN'2008) and Personal Wireless Communications (PWC'2008), Toulouse, France, September 30 - October 2, 2008 / [ed] Zoubir Mammeri, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2008, p. 435-446Conference paper (Refereed)
    Abstract [en]

    Real time mobile communication is challenging due to the inherent limitations of mobile networks. On the other hand the stringent quality of service requirements of real time traffic is highly in demand. Our first contribution is the generic context aware architecture for adaptive real time applications. Adaptation is based on the awareness of context parameters from different layers of the existing protocol stack which involves context exchange among the neighboring layers as well as non-neighboring layers. The architecture comprises of context representation, context acquisition, cross-layer context exchange and context management. Our second contribution is the mobility aware, adaptive Multi-homed Mobile IP. Simulation of adaptive M-MIP was carried out as a proof of concept. Simulation demonstrated that adaptation to mobility was able to decrease Mobile IP handover latency. Further, the results show that the quality of service of real time traffic can be enhanced by using context aware adaptive MIP. The simulation involved with various speeds ranging from pedestrian scenarios to vehicular scenarios. Results are analyzed with variable data rates. The evaluations show that performance of the proposed solution is better compared to conventional MIP in terms of packet loss and throughput of real time traffic.

  • 631.
    Wallin, Stefan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Landen, Leif
    Data Ductus Nord AB.
    Telecom alarm prioritization using neural networks2008In: 22nd International Conference on Advanced Information Networking and Applications - Workshops: AINAW 2008, Los Alamitos, Calif: IEEE Communications Society, 2008, p. 1468-1473Conference paper (Refereed)
    Abstract [en]

    Telecom Service Providers are faced with an overwhelming flow of alarms. Network administrators need to judge which alarms to resolve in order to maintain the service quality. The problem is that it is hard to pick the most important alarms. Which alarms have the highest priority? A solution that automatically assigns priorities to alarms would increase the efficiency of Network Management Centers. We have prototyped a solution that uses neural networks to assign alarm priority. The neural network learns from network administrators by using the manually assigned priorities in trouble-tickets. Our tests are based on live-data from a large mobile service provider and we show that neural networks can learn to assign relevant priorities to 75% of the alarms.

  • 632.
    Kodikara, Ruwini E.
    et al.
    Centre for Distributed Systems and Software Engineering, Monash University.
    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.
    Towards context aware adaptation in wireless networks2008In: Proceedings: The Second International Conference on Mobile Ubiquitous Computing, Systems, Services and Technologies, UBICOMM 2008 : 29 September - 4 October 2008, Valencia, Spain / [ed] Jaime Lloret Mauri, Piscataway, NJ: IEEE Communications Society, 2008, p. 245-250Conference paper (Refereed)
    Abstract [en]

    Next generation ubiquitous computing will comprise of context aware adaptive applications and protocols. There is a need of a generic architecture to cater for the adaptation requirements of increasingly demanding real-time applications and increasing dynamic wireless networks. This paper discusses the adaptive approach supported by CA3RM-Com architecture. CA3RM-Com is the context aware architecture proposed for real-time communication in wireless networks. It addresses the context representation, context acquisition, context exchange,and context management. Specific details of the architecture and referring adaptations that CA3RM-Com can support are discussed. Moreover the extended simulation results of adaptive multi-homed Mobile IP are presented in this paper.

  • 633.
    Witt, Hendrik
    et al.
    University of Bremen.
    Lawo, Michael
    University of Bremen.
    Drugge, Mikael
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Visual feedback and different frames of reference: the impact on gesture interaction techniques for wearable computing2008In: Proceedings of the 10th international conference on Human computer interaction with mobile devices and services / [ed] Henri di Hofte; Ingrid Mulder, New York: ACM Digital Library, 2008, p. 293-300Conference paper (Refereed)
    Abstract [en]

    We present the results of an empirical study investigating the effect of visual feedback and body postures on gesture interaction techniques in a dual task setup found, for example, in wearable computing. The conducted experiment uses a novel apparatus called "Hot Wire" that allows retaining the properties of wearable computing even in laboratory environments. Visual feedback was found to impair user performance and caused users to be caught in an attention demanding closed feedback loop once presented in a head-mounted display. Even though continuous feedback was not necessary for gesture interaction, users were unable to ignore it and remain focused on the primary task. The design of an alternative gesture recognition method using a body-centric frame of reference instead of a conventional static one to improve usability, is shown to have an opposed impact both on the performance and subjective perception of users. The presence of novel devices in gesture interaction, such as data gloves, is found to be a major source of erroneous gesture recognition due to unpredictable user behavior. Our detailed result discussion provides guidelines for designing better gesture interaction.

  • 634.
    Schmidt, Mischa
    et al.
    NEC Laboratories Europe, NEC Europe Ltd., Heidelberg.
    Lamparter, Bernd
    NEC Laboratories Europe.
    Schmid, Stefan
    NEC Laboratories Europe.
    Voice Call Continuity: A Critical Step Towards All-IP Based Next Generation Networks2008In: IEEE GLOBECOM 2008, Global Telecommunications Conference,: New Orleans, Nov. 30 2008-Dec. 4 2008, Piscataway, NJ: IEEE Communications Society, 2008, p. 1-5Conference paper (Refereed)
    Abstract [en]

    The recent developments in the fixed and mobile telecommunication industry, namely the rapid penetration of broadband access and new charging models in the broadband market in conjunction with the success of wireless local area networks and the general trend of fixed and mobile convergence, are transforming the telecommunication landscape. One of the main challenges is to integrate the fixed and mobile technologies in a way that leverages the strengths of different technologies and improves the service experience for the end user. A crucial step for this transformation is to provide adequate support for users to seamlessly switch between network domains and technologies. The main contribution of this paper is a solution that allows a mobile terminal to change from the mobile radio access to the fixed/cable access provided over a local wireless network or vice versa without disrupting an active ongoing voice call. The implementation of the proposed solution was tested and evaluated in an experimental network with real voice calls.

  • 635.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Always best served and managed: research challenges in future mobile multimedia application architectures2007Report (Other academic)
    Abstract [en]

    Demands from users of future generation networks will include seamless access to services across multiple wireless access networks. Handsets and laptops will typically be equipped with several network interfaces and have enough computing power and battery capacity to connect to several access networks simultaneously within and over administrative domains in a multi-homed manner.Existing technologies and solutions solve parts of the problems raised in such a scenario. However, a remaining important research challenge that still needs to be solved is to find an optimal mobility management solution offering terminal mobility as well as session, service, and personal mobility. Furthermore, a uniform and scalable mechanism for quality of service provisioning needs to be defined and integrated in an overall architecture offering differentiated handling of real-time and non real-time flows. The architecture will be based on the Internet Protocol as its least common denominator, but there are still a lot of research questions to be answered.This article surveys existing solutions and outlines future work in the area of cross-layer designed mobility management solutions and integrated quality of service support using a cross-layer design and policy-based approach.

  • 636.
    Hallberg, Josef
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Backlund-Norberg, Mia
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Kristiansson, Johan
    Ericsson Research AB.
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Nugent, Chris
    University of Ulster.
    Creating dynamic groups using context-awareness2007In: Proceedings of the 6th International Conference on Mobile and Ubiquitous Multimedia: December 12 - 14, 2007, Oulu, Finland / [ed] Timo Ojala, Red Hook, NY: Curran Associates, Inc., 2007, p. 42-49Conference paper (Refereed)
    Abstract [en]

    This article presents the conceptual communication model of dynamic groups, that dynamically utilizes three traditional communication metaphors through the use of context-based information. Dynamic groups makes creation, management and usage of groups easy. It enables social network structures to be maintained in both virtual and face-to-face settings as well as in the combination thereof. This article defines the dynamic management of advanced contact lists which can include presence and status information, a/synchronous multimedia communication tools, and methods for structuring social networks. It also contains an initial evaluation and a proposed architecture for technical realisation.

  • 637.
    Schmidt, Mischa
    et al.
    NEC Europe Laboratories.
    Abbadessa, Daniele
    NEC Europe Laboratories.
    Felis, Sebastian
    NEC Europe Laboratories.
    Enriching IMS based IPTV with Virtual Identity Management: Experiences2007Conference paper (Other academic)
  • 638.
    Baraër, Christophe
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Phanse, Kaustubh
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Nykvist, Johan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Birsa, Luka
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    ExPLoIT: exploiting past location information and transitivity for positioning in mobile sensor networks2007In: 2nd International Conference on Communication Systems Software and Middleware, 2007: COMSWARE 2007 ; 7 - 12 Jan. 2007, Bangalore, India, Piscataway, NJ: IEEE Communications Society, 2007Conference paper (Refereed)
    Abstract [en]

    We present a novel distributed range-free technique called ExPLoIT for estimating geographical location of sensor nodes in mobile sensor networks. ExPLoIT is the first positioning technique that exploits location information at regular nodes in addition to using seeds. The key idea is the notion of confidence that a node has in its location estimate which can be used by other nodes for localization. Using Monte Carlo integration, a node estimates its current location and confidence based on its past location and the location information it receives from its neighbors. Node mobility is exploited to transitively localize the network. Our extensive simulation study shows that our proposal outperforms three other state-of-the-art range-free localization techniques under a wide range of conditions. The strength of ExPLoIT is that it is robust to irregular radio propagation, arbitrary seed and node density, and stochastic seed and node mobility; no special hardware is necessary at sensor nodes.

  • 639.
    Nugent, Chris
    et al.
    University of Ulster.
    Davies, Richard
    University of Ulster.
    Hallberg, Josef
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Donnelly, Mark
    University of Ulster.
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Poland, Michael
    University of Ulster.
    Wallace, Jonathan
    University of Ulster.
    Finlay, Dewar
    University of Ulster.
    Mulvenna, Maurice
    University of Ulster.
    Craig, David
    Belfast City Hospital/Queen’s University of Belfast.
    HomeCI - a visual editor for healthcare professionals in the design of home based care2007In: 2007 annual international conference of the IEEE Engineering in Medicine and Biology Society: [EMBC '07] ; Lyon, France, 22 - 26 August 2007, IEEE Communications Society, 2007, p. 2787-2790Conference paper (Refereed)
    Abstract [en]

    The demands of introducing more practical means of managing and monitoring technology within the home environment to support independent living are increasing. Within this paper we present a prototype solution referred to as HomeCI which allows healthcare professionals to establish the conditions within which technology in the home should operate. The HomeCI concept is based on the use of visual notation and has been designed for use by persons with a non technical background. Within the paper we present the design of the first version of the HomeCI visual editor and present the results of a usability study conducted on 4 healthcare professionals.

  • 640.
    Nugent, Chris
    et al.
    University of Ulster.
    Finlay, Dewar
    University of Ulster.
    Davies, Richard
    University of Ulster.
    Wang, Hui
    University of Ulster.
    Zheng, Huiru
    University of Ulster.
    Hallberg, Josef
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Mulvenna, Maurice
    University of Ulster.
    homeML - an open standard for the exchange of data within smart environments2007In: Pervasive Computing for Quality of Life Enhancement: 5th International Conference on Smart Homes and Health Telematics, ICOST 2007, Nara, Japan, June 21 - 23, 2007 ; proceedings / [ed] Takeshi Okadome; Tatsuya Yamazaki; Mounir Makhtari, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2007, p. 121-129Conference paper (Refereed)
    Abstract [en]

    This work describes a potential solution to the problems caused by the heterogeneous nature of the data which may be collected within smart home environments. Such information may be generated at an intra- or interinstitutional level following laboratory testing or based on in-situ evaluations. We offer a solution to this problem in the form of a system/application/format independent means of storing such data. This approach will inevitably support the exchange of data within the research community and form the basis of the establishment of an openly accessible data repository. Within this abstract we present the outline design of homeML, an XML based schema for representation of information within smart homes and through exemplars demonstrate the potential of such an approach. An example of the typical type of software browser required for the data representation is also presented.

  • 641.
    Schmidt, Mischa
    et al.
    NEC Laboratories Europe, NEC Europe Ltd., Heidelberg.
    Wilde, Andreas
    NEC Europe Ltd..
    Schülke, Anett
    NEC Europe Ltd..
    Costa, Henrique
    NEC Portugal.
    IMS interoperability and conformance aspects [IP Multimedia Systems (IMS) Infrastructure and Services]2007In: IEEE Communications Magazine, ISSN 0163-6804, E-ISSN 1558-1896, Vol. 45, no 3, p. 138-142Article in journal (Refereed)
    Abstract [en]

    In this article, we take a closer look at interoperability and conformance aspects when using 3GPP IMS, ETSI TISPAN NGN, and related OMA service enablers. Considering the increasingly important role of 3GPP IMS within mobile and NGN (next generation network) contexts, we highlight the importance of interoperability and conformance testing of IMS products

  • 642.
    Andersson, Karl
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Granlund, Daniel
    Åhlund, Christer
    M4: MultiMedia Mobility Manager: a seamless mobility management architecture supporting multimedia applications2007In: Proceedings of the 6th International Conference on Mobile and Ubiquitous Multimedia: December 12 - 14, 2007, Oulu, Finland / [ed] Timo Ojala, Red Hook, NY: Curran Associates, Inc., 2007, p. 6-13Conference paper (Refereed)
    Abstract [en]

    In this paper, a proof-of-concept and a software architecture, M4 (MultiMedia Mobility Manager), is presented. In short, M4 is offering seamless mobility management to multimedia appli­cations using a variety of wireless access networks. First, M4 is built on multihomed Mobile IP building on the principle of soft handovers. Second, network selection in M4 is based on a network layer metric combining round-trip times and jitter in round-trip times. Third, the end-user can enter its own preferences on network selection through a policy-based extension to the proposed network selection algorithm.The proposed architecture is evaluated in a live heterogeneous networking environment where handover performance is studied in detail. In addition, user-perceived quality of experience for Voice over IP using the M4 software architecture has been studied. Last, downloads of large amount of data using a combination of high and low capacity wireless networks in M4 were studied.Results indicate that the architecture as a whole and the proposed algorithms perform well. M4 can thus be seen as an imple­mentation of the "Always Best Connected" vision.

  • 643.
    Brännström, Robert
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Mobility management in heterogeneous access networks2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis proposes, describes and validates solutions to enhance mobility in heterogeneous access networks. Wireless access networks have become available almost everywhere and current research strives to make them pervasive. Users having wireless access to the Internet are driving the demand for mobile and heterogeneous solutions where services could be accessed from anywhere, any time and from any device. Future wireless connectivity will be provided through a mix of coexisting heterogeneous access network technologies. To enhance mobility in heterogeneous networks this thesis focuses on mobility management systems and connectivity of wireless multi-hop ad hoc networks to the Internet. In a wireless environment with overlapping service areas, mobile nodes need to select which gateway(s) to use to access the wireless infrastructure. The metrics used to select the point of attachment within an access technology are insufficient to compare the capacity of different technologies or multi-hop routes. This thesis proposes, describes and validates solutions to calculating network layer metrics and using them in gateway selection and handover decisions. To enable connectivity of a mobile ad hoc network (MANET) to the Internet, a gateway must bridge the wired single-hop and wireless multi-hop approaches. A MANET enables connectivity to more than one gateway at a time and combined with multihoming it provides seamless handover between subnets. The gateway selection and handover decisions are complicated by the multihoming capabilities. Connectivity to Internet services makes it important to maintain the efficient route to the gateway. It is also important to identify the location of a destination to separate the management of Internet and intra MANET destinations. This thesis proposes,describes and validates solutions to deploying multihomed mobility into MANETs and thereby handling multi-hop gateway discovery, registration of multiple gateways and tunneling to selected gateway(s). The solution maintains gateway connectivity in MANETs by installing routes to gateways using advertisements and manages route discovery based on the destination locality. Both applications with mobility awareness (e.g. SIP phones) and those without it must be supported by a mobility management system. The existence of network layer mobility management can enhance an application layer system. This thesis proposes, describes and validates deployment of a mobility management system with support of both application and network layer mobility. With wireless access networks some technologies might not support some types of applications and a single technology might not cope with all the application demands from a mobile node. Thus the control of individual traffic flows could be used to share the load on multiple access technologies and to direct flows over specified technologies. This thesis proposes, describes and validates solutions to identification and mobility management of individual traffic flows in a heterogeneous network environment. Finally this thesis proposes, describes and validates a deployment proposal of route evaluation and flow control to enable load balancing in wireless multi-hop networks.

  • 644.
    Andersson, Karl
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Sarker, ANM. Zaheduzzaman
    Luleå University of Technology.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Multihomed mobile IPv6: OPNET simulation of network selection and handover timing in heterogeneous networking environments2007In: Proceedings of the Eleventh Annual OPNET Technology Conference: OPNETWORK 2007, 2007Conference paper (Refereed)
  • 645.
    Brännström, Robert
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Andersson, Karl
    Granlund, Daniel
    Multimedia flow mobility in heterogeneous networks using multihomed mobile IP2007In: Journal of Mobile Multimedia, ISSN 1550-4646, E-ISSN 1550-4654, Vol. 3, no 3, p. 218-234Article in journal (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 differences in capabilities and coverage area depending on the access technologies. This paper proposes and evaluates an extension to Mobile IP enabling multihoming, regardless of the access technology. Mobility of multimedia communication in this environment should adapt to changing conditions and be based 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 between access networks and between user devices. Media flows are identified by destination IP address, protocol and port number. Evaluation results are presented both from a simulation study and from a real world prototype implementation using three different wireless access technologies: 802.11, UMTS and 802.16-2004.

  • 646.
    Wallin, Stefan
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Leijon, Viktor
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Multipurpose models for QoS monitoring2007In: 21st International Conference on Advanced Information Networking and Applications Workshops: Niagara Falls, Ontario, Canada, 21 - 23 May 2007 ; proceedings, Los Alamitos, Calif: IEEE Communications Society, 2007, Vol. 1, p. 900-905Conference paper (Refereed)
    Abstract [en]

    Telecom operators face an increasing need for service quality management to cope with competition and complex service portfolios in the mobile sector. Improvements in this area can lead to significant market benefits for operators in highly competitive markets. We propose an architecture for a service monitoring tool, including a time aware formal language for model specification. Using these models allows for increased predictability and flexibility in a constantly changing environment.

  • 647.
    Brännström, Robert
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Zaslavsky, Arkady
    Port-based multihomed mobile IPv6: load-balancing in mobile ad hoc networks2007In: 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, 2007, p. 269-271Conference paper (Refereed)
    Abstract [en]

    With today's heterogeneous access to the Internet, users will move between wired and wireless environments and between infrastructure mode and ad hoc mode of wireless communication. When a mobile node moves from an infrastructure connection and connects multihop to an Internet gateway, the performance will degrade and it may not be able to send all of its traffic via a single gateway. This highlights the need of load-balancing between Internet gateways, especially since the behavior of users today involves a multitude of parallel activities generating multiple flows. This paper proposes a solution that enables distribution of individual traffic flows via different Internet gateways instead of using one single gateway. The proposal includes extensions to Mobile IP in order to handle flow mobility bindings. The performance of the solution is verified by simulation studies.

  • 648.
    Andersson, Karl
    et al.
    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.
    Projekt: Hybrinet@Skellefteå2007Other (Other (popular science, discussion, etc.))
    Abstract [sv]

    Projektet Hybrinet@Skellefteå studerar effektiv multimediedistribution i heterogena nätverksmijöer

  • 649.
    Jayaraman, Prem Prakash
    et al.
    Monash University, Melbourne, VIC.
    Zaslavsky, Arkady
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Delsing, Jerker
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Sensor data collection using heterogeneous mobile devices2007In: 2007 IEEE International Conference on Pervasive Services: [ICPS '07] ; Istanbul, Turkey, 15 - 20 July 2007, Piscataway, NJ: IEEE Communications Society, 2007, p. 161-164Conference paper (Refereed)
    Abstract [en]

    Data collection has always been a major challenge in sensor networks and various techniques have been proposed to enable efficient data collection. One such methodology is the use of mobile elements within the existing infrastructure to enable data collection. The paper proposes the use of existing mobile elements like mobile phones which have enough spare capacity to act as data carriers within a sensor network to carry sensor data. With advent of technology, mobile devices have become so powerful that they can work in a pervasive environment and make decisions based on context information like presence, location etc. Our proposal is an intelligent heterogeneous network in which the sensor nodes act as the data accumulators and the context-aware mobile phones act as data carriers of the sensed data. A framework that enables the mobile node and sensor node communication over Bluetooth is proposed and a p implementation is presented.

  • 650.
    Scholl, Jeremiah
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. Norwegian Centre for Telemedicine.
    McCarthy, John
    University College London.
    Harr, Rikard
    Umeå universitet.
    A comparison of chat and audio in media rich environments2006In: Computer Supported Cooperative Work: Proceedings of the 2006 20th anniversary conference on Computer supported cooperative work, IEEE Communications Society, 2006, p. 323-332Conference paper (Refereed)
    Abstract [en]

    This paper presents two case studies of informal group communication using multimedia conferencing that supports various media including video, audio and chat. The studies provide a comparison of audio and chat as communication medium and present data on usage patterns, user preferences and attitudes. The quantitative and qualitative data collected suggest that chat does have advantages in some situations when used for informal communication along with video. The results provide evidence against the hypothesis that chat is a low bandwidth alternative only used when audio communication is unavailable. This suggests that video mediated chat deserves further attention from designers and the research community, since it is often ignored as a "useful" scenario.

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