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  • 201.
    Badinson (nee Hossieni), David
    KTH, Tidigare Institutioner, Teleinformatik. KTH, Skolan för informations- och kommunikationsteknik (ICT).
    Adding Gigabit Ethernet to an ATM Switch1999Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This document contains the outcome of the final version of my thesis project: Adding Gigabit Ethernet access to an ATM switch. The accelerating growth of LAN (Local Area Network) traffic and growing number of complex and bandwidth hungry applications, such as, fast Interent, video telephony, voice over Internet, etc., is pushing  network administrators to look to high-speed network technologies.

    The Gigabit Ethernet and ATM are two dominant technologies in network backbone which are operating at gigabit-speed. These two technologies are considered to be competitors, but in reality they are appropriate for different applications and they are not equal substitute for each other. What we can do in this connection is to take up the advantages of both technologies and try to on somehow integrate them, in order to achieve high performance and powerful networks which are extremely demanded for future applications.

    The purpose with this project was to study the ATM and Gigabit Ethernet technologies and investigate the possibility of integrating them. This report includes an introduction to both technologies and design for a Gigabit Ethernet access card to an ATM switch. The document presents the including components in the card and gives a detailed description for each of components.

  • 202.
    Baecklund, Fredrik
    KTH, Tidigare Institutioner, Teleinformatik.
    Software architecture for a scalable carrier class edge router1999Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    With the rapid growth of the Internet in the recent years and the expected future growth puts greater demands on high performance access and routing  technologies. The Ericsson AXI 510 Edge Router is a step in the right direction but to provide enough performance for future demands, a highly scalable system has to be designed. This new system is probably going to be based on a distributed architecture.

    In this MSc thesis the author discusses possible ways of designing a scalable distributed edge router software architecture and what implications the distributed architecture has on different edge router applications such as Network Address Translation, tunnel termination and management etc. Furthermore, the author presents a design proposal for a fully distributed architecture.

  • 203.
    Baetens, Jens
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Improving the Quality of Web Content through Automated Metrics: An attempt to process course pages at the kth.se website2015Rapport (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    Today many organizations make a great deal of content available via a web interface. For this project the main scope will be the public web of KTH Royal Institute of Technology. KTH has lots of data available online. The problem that occurs is that the people who write this content do not get feedback about what they post. The idea of this project is to change that and by giving the responsible person(s) feedback about their content.

    The main goal of the project is keeping track of changes of web pages. For example, each course has its own content and information pages - which can be changed by the person(s) responsible for the course. When pages are available in two languages and changes are made to one of them the logical expectation would be that the other language has to be changed as well. However, in the current system there is no systematic way that this change occurs or that someone would be reminded when only one version changed. Similarly for other content pages, although these might not be in multiple languages it would be interesting to see how often a page is updated and to notify the responsible person(s) that a certain page has not been updated in quite some time.

    A secondary goal of this project is to provide a proof of concept implementation of a tool that can automatically access web page in KTH Social (a locally developed web service) – thus enabling users to write code that can access, modify, and annotate web pages. Such a tool could be used to compute readability scores for each page and then annotate the page with this score.

    The code that was implemented for this project accomplished both goals. Some suggestions are made for how this process can be improved and how alternatively this processing could be done by working directly on the databases used to produce dynamic content.

  • 204.
    Bagci, Ibrahim
    et al.
    Lancaster University.
    Raza, Shahid
    SICS.
    Chung, Antony
    Univ. of Lancaster.
    Roedig, Utz
    Univ. of Lancaster.
    Voigt, Thiemo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Combined Secure Storage and Communication for the Internet of Things2013Inngår i: IEEE International Conference on Sensing, Communication and Networking (IEEE SECON), 2013Konferansepaper (Fagfellevurdert)
  • 205. Bagger, Reza
    Noise reduction and tilt reduction in passive FET multi-phase mixers2012Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    The noise response in a passive mixer circuit is improved by discharging the switching transistors in the mixer circuit in an appropriate time slot prior to activation. In addition to improving the noise response, tilt in conversion gains and linearity can be reduced. A passive mixer circuit includes bypass switches arranged in proximity to the switching transistors that make up the mixer core. These bypass switches, which are activated in intervals just prior to the active intervals of their neighboring switching transistors, discharge to ground accumulated charges on the switching transistors or on reactive components around switches.

  • 206.
    Bagger, Reza
    et al.
    Infineon Technology Nordic AB, Kista, Sweden.
    Hahn, T
    Wallace, R
    Edevarn, L
    System-in-package synthesizer for PCS/DCS application2007Inngår i: European Microwave Week 2007 Conference Proceedings, IEEE , 2007, s. 520-523Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The article presents a system-in-package (SiP) approach for synthesizer system module used in frequency down-and up-conversion of PCS/DCS radio base station applications using low-temperature co-fired ceramic (LTCC). The hybrid module benefits from the latest qualified production technology based on multilayer LTCC technology. LTCC permits a relatively high level of circuit integration in which different parts of the synthesizer such as the VCO, buffer amplifier, loop filter, PLL circuit, switch, and voltage regulator are integrated in a single substrate of 21 x 16 x 4 mm3. The module exhibits minimum RF tuning sections, improved performance repeatability, excellent RF performance, and good low phase noise. The module covers 1800 MHz Rx/Tx and 1900 MHz Rx/Tx frequency bands. Adoption of the synthesizer to upper or lower frequency band is possible by means of few component changes in a novel tuneable resonator structure. The module's design concept defines 4 commercial products which is included in Infineon's portfolio of wireless infrastructure circuit solutions for PCS/DCS radio basestation applications.

  • 207. Bagger, Reza
    et al.
    Sahl, Stefan
    Signal generator and associated phase shift apparatus and method2013Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    It is presented a signal generator for providing a first signal on a first output and a second signal on a second output wherein the first signal and the second signal are provided with phase shift relative to each other. The signal generator comprises: a control loop controller; a comparator; a phase shifter, the phase shifter being arranged to provide the first signal on the first output and the second signal on the second output; and a phase error detector, the inputs of which are connected to the outputs of the phase shifter and the output of which is connected to an input of the control loop controller. The output of the control loop controller is connected in a feedback loop to a first input of the comparator, and a second input of the comparator is arranged to be connected to an alternating current source.

  • 208. Bagger, Reza
    et al.
    Wallace, Richard
    Hahn, Tobias
    Palima, Dante
    Resonator for a voltage controlled oscillator and manufacturing method thereof2007Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    An LC resonator (117; 122) for a voltage controlled oscillator (13; 116) has an inductive transmission line 31; 51), and input and output ports (33 a-b; 53 a-b) connected to the transmission line, wherein the transmission line is grounded (G) in at least one end portion thereof. The inductive transmission line has a plurality of connection ports (P) that are capable of being connected to each other or to ground in order to tune the resonance frequency of the LC resonator from one frequency band to another. Further, a trimming capacitor (C) may be interconnected in the transmission line in order to further tune the resonance frequency of the LC resonator. Preferably, the LC resonator is formed as a microstrip or strip line structure in essentially a C or S shape on a laminate substrate (101-103).

  • 209.
    Baglee, David
    et al.
    University of Sunderland, UK.
    Gorostegui, Unai
    Mondragon University, Spain.
    Jantunen, Erkki
    VTT Technical Research Centre of Finland, Finland.
    Campos, Jaime
    Linnéuniversitetet, Fakulteten för teknik (FTK), Institutionen för informatik (IK).
    Sharma, Pankaj
    Indian Institute of Technology Delhi, India.
    Optimizing Condition Monitoring of Big Data Systems2017Inngår i: Proceedings of the 2017 International Conference on Data Mining: DMIN'17 / [ed] Robert Stahlbock, Mahmoud Abou-Nasr, Gary M. Weiss, CSREA Press, 2017, s. 127-131Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Industrial communication networks are common in a number of manufacturing organisations. The high availability of these networks is crucial for smooth plant operations. Therefore local and remote diagnostics of these networks is of primary importance in determining issues relating to plant reliability and availability. Condition Monitoring (CM) techniques when connected to a network provide a diagnostic system for remote monitoring of manufacturing equipment. The system monitors the health of the network and the equipment and is therefore able to predict performance. However, this leads to the collection, storage and analyses of large amounts of data, which must provide value. These large data sets are commonly referred to as Big Data. This paper presents a general concept of the use of condition monitoring and big data systems to show how they complement each other to provide valuable data to enhance manufacturing competiveness.

  • 210.
    Baglee, David
    et al.
    University of Sunderland, UK.
    Gorostegui, Unai
    Mondragon University, Spain.
    Jantunen, Erkki
    VTT Technical Research Centre of Finland, Finland.
    Sharma, Pankaj
    Indian Institute of Technology Dehli, India.
    Campos, Jaime
    Linnéuniversitetet, Fakulteten för teknik (FTK), Institutionen för informatik (IK).
    How can SMEs adopt a new method to advanced maintenance strategies: A Case study approach2017Inngår i: 30th International Congress & Exhibition on Condition Monitoring and Diagnostic Engineering Management COMADEM, July 10th-13th 2017, University of Central Lancashire, 2017Konferansepaper (Fagfellevurdert)
  • 211.
    Bai, Chumeng
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Kommunikationssystem, CoS, Radio Systems Laboratory (RS Lab).
    Evaluation and Improvement of Decentralized Congestion Control for Multiplatooning Application2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Platooning has the potential to be a breakthrough in increasing road capacity and reducing fuel consumption, as it allows a chain of vehicles to closely follow each other on the road. When the number of vehicles increases, platoons will follow one another in what is referred to as multiplatooning. Many Cooperative Intelligent Transportation Systems (C-ITS) applications rely on periodically exchanged beacons among vehicles to improve traffic safety. However, as the number of connected vehicles increases, the network may become congested due to periodically exchanged beacons. Therefore, without some congestion control method, safety critical messages such as Cooperative Awareness Messages (CAMs) may not be delivered on time in high vehicle density scenarios. Both the European Telecommunications Standards Institute (ETSI) and the Institute of Electrical and Electronics Engineers (IEEE) have been working on different standards to support vehicular communication. ETSI dened the Decentralized Congestion Control (DCC) mechanism which adapts transmission parameters (message rate, transmit data rate, and transmit power, etc.) to keep channel load under control. ETSI DCC utilizes a three-state machine with RELAXED, ACTIVE, and RESTRICTIVE states. In this thesis, we implemented this three-state machine by adapting the message rate based on the channel busy ratio (CBR). We name this message-rate based three-state machine DCC-3. DCC-3 has the ability to control channel load; however, it has unfairness and instability problems due to the dramatic parameter changes between states. Therefore, we divided the ACTIVE state of DCC-3 into ve sub-states, and refer to this as DCC-7. We benchmarked DCC-3 against static beaconing (STB), dynamic beaconing (DynB), LInear MEssage Rate Integrated Control (LIMERIC), and DCC-7 using different evaluation metrics with different numbers of platoons. Our results from the Plexe simulator demonstrate that DCC-7 has the best performance when considering all evaluation metrics, including CBR, Inter-reception time (IRT), collisions, safe time ratio, and fairness. Furthermore, we found using transmit power control could greatly improve the performance of CBR and collision rates.

  • 212.
    Bai, Xin
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Broadband Wireless Access in Disaster Emergency Response2006Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The “WLAN in Disaster Emergency Response” (WIDER) project has developed and implemented an emergency communication system. It provides network and communication services to relief organizations. In order to guarantee the stable and efficient connectivity with a high quality of service (QoS) for the end user, and to make the WIDER system more adaptive to the disaster area, the IEEE 802.16 specification based broadband wireless access solution is adopted. This thesis work aims at evaluating and testing the WIDER system integrated with WiMAX. By learning and analyzing the technology, the benefits and perspective for WIDER using WiMAX are described. A WiMAX solution was configured and integrated into the WIDER system. A series of tests and measurements provide us the performance of the WiMAX solution in throughput, QoS, and reality. The tests helped us to learn and verify the improvements for WIDER due to WiMAX.

  • 213.
    Baig, Roger
    et al.
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Freitag, Felix
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain .
    Moll, Agusti
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Navarro, Leandro
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain.
    Pueyo, Roger
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Vlassov, Vladimir
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Programvaruteknik och Datorsystem, SCS.
    Cloud-based community services in community networks2016Inngår i: 2016 International Conference on Computing, Networking and Communications, ICNC 2016, IEEE conference proceedings, 2016, s. 1-5, artikkel-id 7440621Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Wireless networks have shown to be a cost effective solution for an IP-based communication infrastructure in under-served areas. Services and application, if deployed within these wireless networks, add value for the users. This paper shows how cloud infrastructures have been made operational in a community wireless network, as a particular case of a community cloud, developed according to the specific requirements and conditions of the community. We describe the conditions and requirements of such a community cloud and explain our technical choices and experience in its deployment in the community network. The user take-up has started, and our case supports the tendency of cloud computing moving towards the network edge.

  • 214.
    Baig, Roger
    et al.
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Freitag, Felix
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain .
    Moll, Agusti
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Navarro, Leandro
    Department of Computer Architecture. Universitat Politecnica de Catalunya. Barcelona, Spain.
    Pueyo, Roger
    Fundacio Privada per la Xarxa Lliure, Oberta i Neural Guifi.net. Mas l’Esperanca, 08503 Gurb, Catalonia.
    Vlassov, Vladimir
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Programvaruteknik och Datorsystem, SCS.
    Community network clouds as a case for the IEEE Intercloud standardization2015Inngår i: 2015 IEEE Conference on Standards for Communications and Networking, CSCN 2015, 2015, s. 269-274, artikkel-id 7390456Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The IEEE P2302 Intercloud WG conducts work since 2011 on the project Standard for Intercloud Interoperability and Federation with the goal to define a standard architecture and building components for large-scale interoperability of independent cloud providers. While the standardization process has achieved fine-grained definitions of several Intercloud components, a deployment of the Intercloud to demonstrate the architectural feasibility is not yet operational. In this paper, we describe a deployed community network cloud and we show how it matches in several aspects the vision of the Intercloud. Similar to the Intercloud, the community network cloud consists of many small cloud providers, which for interoperability use a set of common services. In this sense, the community network cloud is a real use case for elements that the Intercloud standardization WG envisions, and can feed back to and even become part of the Intercloud. In fact, a study on Small or Medium Enterprise (SME) provided commercial services in the community network cloud indicates the importance of the success of the Intercloud standardization initiative for SMEs.

  • 215.
    Balador, Ali
    et al.
    SICS Swedish ICT Västerås AB, Västerås, Sweden. & Polytechnic University of Valencia, Valencia, Spain.
    Böhm, Annette
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS).
    Calafate, Carlos T.
    Polytechnic University of Valencia, Valencia, Spain.
    Cano, Juan-Carlos
    Polytechnic University of Valencia, Valencia, Spain.
    A Reliable Token-Based MAC Protocol for V2V Communication in Urban VANET2016Inngår i: 2016 IEEE 27TH ANNUAL INTERNATIONAL SYMPOSIUM ON PERSONAL, INDOOR, AND MOBILE RADIO COMMUNICATIONS (PIMRC), Piscataway: IEEE , 2016, s. 1586-1591Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Safety applications developed for vehicular environments require every vehicle to periodically broadcast its status information (beacon) to all other vehicles, thereby avoiding the risk of car accidents in the road. Due to the high requirements on timing and reliability posed by traffic safety applications, the current IEEE 802.11p standard, which uses a random access Medium Access Control (MAC) protocol, faces difficulties to support timely and reliable data dissemination in vehicular environments where no acknowledgement or RTS/CTS (Request-to-Send/Clear-to-Send) mechanisms are adopted. In this paper, we propose the Dynamic Token-Based MAC (DTB-MAC) protocol. It implements a token passing approach on top of a random access MAC protocol to prevent channel contention as much as possible, thereby improving the reliability of safety message transmissions. Our proposed protocol selects one of the neighbouring nodes as the next transmitter; this selection accounts for the need to avoid beacon lifetime expiration. Therefore, it automatically offers retransmission opportunities to allow vehicles to successfully transmit their beacons before the next beacon is generated whenever time and bandwidth are available. Based on simulation experiments, we show that the DTB-MAC protocol can achieve better performance than IEEE 802.11p in terms of channel utilization and beacon delivery ratio for urban scenarios.

  • 216.
    Balador, Ali
    et al.
    Högskolan i Halmstad, Akademin för informationsteknologi. Universitat Politecnica de València, València, Spain.
    Böhm, Annette
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Uhlemann, Elisabeth
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES). Mälardalen University, Västerås, Sweden.
    Calafate, Carlos T.
    Universitat Politecnica de València, València, Spain.
    Cano, Juan-Carlos
    Universitat Politecnica de València, València, Spain.
    A Reliable Token-Based MAC Protocol for Delay Sensitive Platooning Applications2015Inngår i: 2015 IEEE 82nd Vehicular Technology Conference (VTC2015-Fall), [S.l.]: IEEE, 2015, artikkel-id 7390813Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Platooning is both a challenging and rewarding application. Challenging since strict timing and reliability requirements are imposed by the distributed control system required to operate the platoon. Rewarding since considerable fuel reductions are possible. As platooning takes place in a vehicular ad hoc network, the use of IEEE 802.11p is close to mandatory. However, the 802.11p medium access method suffers from packet collisions and random delays. Most ongoing research suggests using TDMA on top of 802.11p as a potential remedy. However, TDMA requires synchronization and is not very flexible if the beacon frequency needs to be updated, the number of platoon members changes, or if retransmissions for increased reliability are required. We therefore suggest a token-passing medium access method where the next token holder is selected based on beacon data age. This has the advantage of allowing beacons to be re-broadcasted in each beacon interval whenever time and bandwidth are available. We show that our token-based method is able to reduce the data age and considerably increase reliability compared to pure 802.11p. © 2015 IEEE.

  • 217.
    Balador, Ali
    et al.
    Polytechnic University of Valencia, Valencia, Spain.
    Böhm, Annette
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Uhlemann, Elisabeth
    Mälardalen University, Västerås, Sweden.
    Calafate, Carlos T.
    Polytechnic University of Valencia, Valencia, Spain.
    Ji, Yusheng
    National Institute of Informatics, Tokyo, Japan.
    Cano, Juan-Carlos
    Polytechnic University of Valencia, Valencia, Spain.
    Manzoni, Pietro
    Polytechnic University of Valencia, Valencia, Spain.
    An Efficient MAC Protocol for vehicle platooning in automated highway systems2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Lately, all the top truck manufacturers are investing considerable resources in the research and development of platooning systems which would allow vehicles to save fuel and improve safety by travelling in a close-following manner. The platooning system requires frequent and reliable vehicle-to-vehicle communications. As platooning takes place in a vehicular ad hoc network, the use of IEEE 802.11p is close to mandatory. However, the 802.11p medium access method suffers from packet collisions and random delays. Most ongoing research suggests using TDMA on top of 802.11p as a potential remedy. However, TDMA requires synchronization and is not very flexible if the beacon frequency needs to be updated, the number of platoon members changes, or if re-transmissions for increased reliability are required. We therefore suggest a token-passing medium access method where the next token holder is selected based on beacon data age. This has the advantage of allowing beacons to be re-broadcasted in each beacon interval whenever time and bandwidth are available. We show that our token-based method is able to reduce the data age and considerably increase reliability considerably compared to pure 802.11p.

  • 218.
    Balasubramaniam, Sasitharan
    et al.
    Tampere University of Technology, Tampere, Finland .
    Lyamin, Nikita
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Kleyko, Denis
    Luleå University of Technology, Luleå, Sweden.
    Skurnik, Mikael
    University of Helsinki, Helsinki, Finland .
    Vinel, Alexey
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Koucheryavy, Yevgeni
    Tampere University of Technology, Tampere, Finland .
    Exploiting bacterial properties for multi-hop nanonetworks2014Inngår i: IEEE Communications Magazine, ISSN 0163-6804, E-ISSN 1558-1896, Vol. 52, nr 7, s. 184-191Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Molecular communication is a relatively new communication paradigm for nanomachines where the communication is realized by utilizing existing biological components found in nature. In recent years researchers have proposed using bacteria to realize molecular communication because the bacteria have the ability to swim and migrate between locations, carry DNA contents (i.e. plasmids) that could be utilized for information storage, and interact and transfer plasmids to other bacteria (one of these processes is known as bacterial conjugation). However, current proposals for bacterial nanonetworks have not considered the internal structures of the nanomachines that can facilitate the use of bacteria as an information carrier. This article presents the types and functionalities of nanomachines that can be utilized in bacterial nanonetworks. A particular focus is placed on the bacterial conjugation and its support for multihop communication between nanomachines. Simulations of the communication process have also been evaluated, to analyze the quantity of bits received as well as the delay performances. Wet lab experiments have also been conducted to validate the bacterial conjugation process. The article also discusses potential applications of bacterial nanonetworks for cancer monitoring and therapy. © 2014 IEEE.

  • 219. Baldini, Gianmarco
    et al.
    Kounelis, Ioannis
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS. European Commiss, Joint Res Ctr, Inst Protect & Secur Citizen, Ispra, VA, Italy..
    Loeschner, Jan
    Tallacchini, Mariachiara
    European Citizens and Their Trust in Social Networks2014Inngår i: Learning and Collaboration Technologies. Technology-Rich Environments for Learning and Collaboration: First International Conference, LCT 2014, Held as Part of HCI International 2014, Heraklion, Crete, Greece, June 22-27, 2014, Proceedings, Part II, Springer International Publishing , 2014Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In information and communication technology (ICT) trust has been considered as a crucial component of digital interactions. Trust has been dissected in a variety of potential meanings and dimensions and through the merging of trust in humans and trust in machines. In this paper, we investigate the role and the aggregation of trust in social networks and blogs and how it relates to knowledge production, and its connections to concepts such as reputation and sustainability in the European context. Moreover, we discuss knowledge production in information and communication technology and its relationship to user trust. We develop a view on the co-production of knowledge and trust and propose a policy management framework to support the users in their trusted use of social networks and blogs. This is presented based on an e-health use case analysis considering web based reputation and developing a new reputation scheme.

  • 220. Baliosian, J.
    et al.
    Stadler, Rolf
    KTH, Skolan för elektro- och systemteknik (EES), Kommunikationsnät.
    Decentralized configuration of neighboring cells for radio access networks2007Inngår i: 2007 IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks, WOWMOM, IEEE , 2007, s. 4351740-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In order to execute a handover processes in a Radio Access Network, each cell has a configured list of neighbors to which such handovers are made. Rapid re-configuration of the neigh-borhood list in response to network failures and other events is currently not possible. To address this problem, this paper suggests an autonomic approach for dynamically configuring neighboring cell lists and introduces a decentralized, three-layered framework. As a key element of this framework, a novel probabilistic protocol that detects and continuously tracks the coverage overlaps among cells is presented and evaluated. The protocol, called DOC, maintains a distributed graph of over-lapping cells. Due to using Bloom fillers and aggregation techniques, it exhibits a low traffic and computational overhead. A first series of simulation studies suggests that DOC is scalable with respect to network size and the number of terminals.

  • 221. Bang, I.
    et al.
    Kim, Su Min
    KTH, Skolan för elektro- och systemteknik (EES), Signalbehandling.
    Sung, D. K.
    Opportunistic user selection with adaptive jamming for secure communication in heterogeneous networks2015Inngår i: IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC, IEEE conference proceedings, 2015, s. 42-46Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper, we propose an opportunistic user selection criterion to obtain a multiuser diversity gain for secure communication. At the same time, we also propose a strategy for utilizing a small base station in heterogeneous networks as a helper or a jammer adaptively. Our approach is to maximize the secrecy achievable rate based on an analytically derived lower bound instead of the original objective function due to its complexity. Based on a simple proposed user selection criterion considering both macro and small base stations, we propose two jamming strategies according to knowledge of eavesdropper's channel: adaptive jamming and probabilistic jamming strategies. Through simulations in two scenarios, it is shown that our proposed user selection and jamming schemes provide a good performance gain in terms of secrecy achievable rate.

  • 222. Bao, J.
    et al.
    Ma, Z.
    Xiao, Ming
    KTH, Skolan för elektro- och systemteknik (EES), Teknisk informationsvetenskap. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Tsiftsis, T. A.
    Zhu, Z.
    Performance analysis of uplink sparse code multiple access with iterative multiuser receiver2017Inngår i: 2017 IEEE International Conference on Communications, ICC 2017, Institute of Electrical and Electronics Engineers (IEEE), 2017, artikkel-id 7996537Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper investigates the asymptotic performance of bit-interleaved coded modulation (BICM) with iterative multiuser detection and decoding in uplink sparse code multiple access (SCMA) systems. The extrinsic information transfer (EXIT) characteristics analysis of the joint multiuser detector for SCMA is provided, and shows that the average detection reliability for multiple users converges to the single-user case, if ideal feedback from the decoder is available to the detector. We develop a tight analytical bound on the convolutionally encoded bit-error rate (BER) for independent Rayleigh fadings, based on the single-user bound with arbitrary multidimensional constellations. Moreover, we analyze the achievable coding and diversity gains of the SCMA-BICM system with iterative receiver. Simulations are carried out to verify the effectiveness of the analysis.

  • 223.
    Bao, Jinchen
    et al.
    Southwest Jiaotong Univ, Prov Key Lab Informat Coding & Transmiss, Chengdu 611731, Sichuan, Peoples R China..
    Ma, Zheng
    Southwest Jiaotong Univ, Prov Key Lab Informat Coding & Transmiss, Chengdu 611731, Sichuan, Peoples R China..
    Xiao, Ming
    Royal Inst Technol, Dept Commun Theory, S-10044 Stockholm, Sweden..
    Ding, Zhiguo
    Univ Lancaster, Sch Comp & Commun, Lancaster LA1 4YW, England..
    Zhu, Zhongliang
    Southwest Jiaotong Univ, Prov Key Lab Informat Coding & Transmiss, Chengdu 611731, Sichuan, Peoples R China..
    Performance Analysis of Uplink SCMA With Receiver Diversity and Randomly Deployed Users2018Inngår i: IEEE Transactions on Vehicular Technology, ISSN 0018-9545, E-ISSN 1939-9359, Vol. 67, nr 3, s. 2792-2797Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper considers the performance analysis of sparse code multiple access (SCMA) with receive diversity arrays and randomly deployed users in a cellular uplink scenario. The impact of path loss on the performance of SCMA is characterized, by assuming independent Rayleigh fading and joint maximum likelihood (ML) receivers. A tight upper bound on the probability of symbol detection error is derived, and the achievable diversity and coding gains are investigated. The analytical results are validated by using simulations, and show that a diversity order which is equal to the product of the number of receive antennas and the signal-space diversity can be achieved, and the large-scale path-loss decreases only the coding gain.

  • 224.
    Barac, Filip
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    LPED: Channel Diagnostics in WSN Through Channel Coding and Symbol Error Statistics2014Inngår i: IEEE ISSNIP 2014 - 2014 IEEE 9th International Conference on Intelligent Sensors, Sensor Networks and Information Processing, Conference Proceedings, Singapore: IEEE Sensors Council, 2014, s. 1-6Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Three major obstacles to wireless communication are electromagnetic interference, multipath fading and signal attenuation. The former stems mainly from collocated wireless systems operating in the same frequency band, while the latter two originate from physical properties of the environment. Identifying the source of packet corruption and loss is crucial, since the adequate countermeasures for different types of threats are essentially different. This problem is especially pronounced in industrial monitoring and control applications, where IEEE 802.15.4 communication is expected to deliver data within tight deadlines, with minimal packet loss. This work presents the Lightweight Packet Error Discriminator (LPED) that distinguishes between errors caused by multipath fading and attenuation, and those inflicted by IEEE 802.11 interference. LPED uses Forward Error Correction to determine the symbol error positions inside erroneously received packets and calculates the error density, which is then fed to a discriminator for error source classification. The statistical constituents of LPED are obtained from an extensive measurement campaign in two different types of industrial environments. The classifier incurs no overhead and in ≥90% of cases a single packet is sufficient for a correct channel diagnosis. Experiments show that LPED accelerates link diagnostics by at least 190%, compared to the relevant state-of-the-art approaches.

  • 225.
    Barac, Filip
    et al.
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. ABB Corp Res, S-72178 Vasteras, Sweden.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Scrutinizing Bit- and Symbol-Errors of IEEE 802.15.4 Communication in Industrial Environments2014Inngår i: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 63, nr 7, s. 1783-1794Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The knowledge of error nature in wireless channels is an essential constituent of efficient communication protocol design. To this end, this paper is the first comprehensive bit- and symbol-level analysis of IEEE 802.15.4 transmission errors in industrial environments. The intention with this paper is to extract the error properties relevant for future improvements of wireless communication reliability and coexistence of radio systems in these harsh conditions. An extensive set of bit-error traces was collected in a variety of scenarios and industrial environments, showing that error behavior is highly dependent on the cause of packet corruption. It is shown that errors inflicted by multipath fading and attenuation exhibit different properties than those imposed by IEEE 802.11 interference. The statistical behavior of these two patterns is concurrently investigated in terms of differences in bit-error distribution, error burst length, channel memory length, and the scale of packet corruption. With these conclusions at hand, abiding to the computational constraints of embedded sensors and the statistical properties of bit-errors, a Reed-Solomon $(15,k)$ block code is chosen to investigate the implications of bit-error nature on practical aspects of channel coding and interleaving. This paper is concluded by a number of findings of high practical relevance, concerning the optimal type, depth, and meaningfulness of interleaving.

  • 226.
    Barac, Filip
    et al.
    Ericsson AB.
    Gidlund, Mikael
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Zhang, Tingting
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
    Sisinni, Emiliano
    University of Brescia.
    Error Manifestation in Industrial WSN Communication and Guidelines for Countermeasures2017Inngår i: Wireless Sensor Systems for Extreme Environments: Space, Underwater, Underground and Industrial / [ed] H. F. Rashvand and A. Abedi, John Wiley & Sons, 2017Kapittel i bok, del av antologi (Fagfellevurdert)
  • 227.
    Barac, Filip
    et al.
    Mid Sweden University.
    Yu, Kan
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Gidlund, Mikael
    ABB, Corporate Research.
    Åkerberg, Johan
    ABB, Corporate Research.
    Björkman, Mats
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Towards Reliable and Lightweight Communication in Industrial Wireless Sensor Networks2012Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In this paper we address the issues of timeliness and transmission reliability of existing industrial communication standards. We combine a Forward Error Correction coding schemeon the Medium Access Control layer with a lightweight routing protocol to form an IEEE 802.15.4-conformable solution, whichcan be implemented into already existing hardware without violating the standard. After laying the theoretical foundations,we conduct a performance evaluation of the proposed solution.The results show a substantial gain in reliability and reducedlatency, compared to the uncoded transmissions, as well ascommon Wireless Sensor Network routing protocols.

  • 228.
    Barbette, Tom
    University of Liege.
    Architecture for programmable network infrastructure2018Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    Software networking promises a more flexible network infrastructure, poised to leverage the computational power available in datacenters. Virtual Net- work Functions (VNF) can now run on commodity hardware in datacenters instead of using specialized equipment disposed along the network path. VNFs applications like stateful firewalls, carrier-grade NAT or deep packet inspection that are found “in-the-middle”, and therefore often categorized as middleboxes, are now software functions that can be migrated to reduce costs, consolidate the processing or scale easily. But if not carefully implemented, VNFs won’t achieve high-speed and will barely sustain rates of even small networks and therefore fail to fulfil their promise. As of today, out-of-the-box solutions are far from efficient and cannot handle high rates, especially when combined in a single host, as multiple case studies will show in this thesis. We start by reviewing the current obstacles to high-speed software net- working. We leverage current commodity hardware to achieve what seemed impossible to do in software not long ago and made software solutions be- lieved unworthy and untrusted by network operators. Our work paves the way for building a proper software framework for a programmable network infrastructure that can be used to quickly implement network functions. We built FastClick, a faster version of the Click Modular Router, that allows fast packet processing thanks to a careful integration of fast I/O frame- works and a deep study of interactions of their features. FastClick proposes a revised, easier to use execution model that hides multi-queueing and sim- plifies multithreading using a thread traversal analysis of the configuration. We propose tailored network-specific multi-threaded algorithms that enable parallel high-speed networking. We build a new retro-compatible batching implementation, and avoid system calls “left over” by previous work. We then build MiddleClick, an NFV dataplane built on top of FastClick. It combines VNFs along a service chain to use a common subsystem that implements shared features such as classification and session handling, but makes sure no feature is applied that isn’t absolutely needed by one of the VNFs. E.g., the classification is optimized to be minimal and only needs to be done once for all VNFs. E.g., if no VNF needs TCP reconstruction, that reconstruction won’t happen. We propose an algorithm to enable a per-session, per-VNF “scratchpad”. Only the minimal amount of state is declared and accessible in predictable locations using a per-VNF offset into the “scratchpad” for fast lookups across the chain. MiddleClick also offers new flow abstractions and ways to handle sessions that enable fast and easy development of new middlebox functions that can handle many flows in parallel. Cooperation, consolidation and using the hardware in an appropriate way may not always be enough. This thesis finally explores how to use classi- fication hardware such as smart NICs and SDN switches to accelerate the processing of the combined service chain, removing the need for software classification. While this work mostly relies on known high-level NFV dataplane principles and proposes a few new ones, it is one of the most low-level work in the field, leading to precise implementation considerations yielding very high performance results. Both FastClick and MiddleClick are available as Open Source projects and constitute an important contribution to the state of the art. Multiple leading edge use cases are built to show how the prototype can be used to build fast and efficient solutions quickly.

  • 229. Barkowsky, M
    et al.
    Brunnström, Kjell
    Acreo ICT Swedish AB.
    Ebrahimi, T
    Karam, L
    Lebreton, P
    Le Callet, P
    Perkis, A
    Raake, A
    Subedar, M
    Wang, Kun
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
    Xing, L
    You, J
    Subjective and Objective Visual Quality Assessment in the Context of stereoscopic 3DTV2013Inngår i: 3DTV System with Depth-Image-Based Rendering / [ed] Yu, L., Tanimoto, M., and Zhu, C., Springer, 2013, s. 413-437Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Subjective and objective visual quality assessment in the context of stereoscopic three-dimensional TV (3D-TV) is still in the nascent stage and needs to consider the effect of the added depth dimension. As a matter of fact, quality assessment of 3D-TV cannot be considered as a trivial extension of two-dimensional (2D) cases. Furthermore, it may also introduce negative effects not experienced in 2D, e.g., discomfort or nausea. Based on efforts initiated within the cost action ICT 1003 QUALINET, this chapter discusses current challenges in relation to subjective and objective visual quality assessment for stereo-based 3D-TV. Two case studies are presented to illustrate the current state of the art and some of the remaining challenges. © Springer Science+Business Media New York 2013. All rights are reserved.

  • 230.
    Barkowsky, M
    et al.
    University of Nantes, France.
    Masala, E
    Politecnico di Torino, Italy.
    Van Wallendael, G
    Ghent University - iMinds, Belgium.
    Brunnström, Kjell
    Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Acreo Swedish ICT AB, Sweden .
    Staelens, N
    Ghent University - iMinds, Belgium.
    Le Callet, P
    University of Nantes, France.
    Objective Video Quality Assessment - Towards large scale video database enhanced model development.2015Inngår i: IEICE transactions on communications, ISSN 0916-8516, E-ISSN 1745-1345, Vol. E98-B, nr 1, s. 2-11Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The current development of video quality assessment algorithms suffers from the lack of available video sequences for training, verification and validation to determine and enhance the algorithm's application scope. The Joint Effort Group of the Video Quality Experts Group (VQEG-JEG) is currently driving efforts towards the creation of large scale, reproducible, and easy to use databases. These databases will contain bitstreams of recent video encoders (H.264, H.265), packet loss impairment patterns and impaired bitstreams, pre-parsed bitstream information into files in XML syntax, and well-known objective video quality measurement outputs. The database is continuously updated and enlarged using reproducible processing chains. Currently, more than 70,000 sequences are available for statistical analysis of video quality measurement algorithms. New research questions are posed as the database is designed to verify and validate models on a very large scale, testing and validating various scopes of applications, while subjective assessment has to be limited to a comparably small subset of the database. Special focus is given on the principles guiding the database development, and some results are given to illustrate the practical usefulness of such a database with respect to the detailed new research questions.

  • 231. Baroffio, L.
    et al.
    Canclini, A.
    Cesana, M.
    Redondi, A.
    Tagliasacchi, M.
    Dán, György
    KTH, Skolan för elektro- och systemteknik (EES), Kommunikationsnät.
    Eriksson, Emil
    KTH, Skolan för elektro- och systemteknik (EES), Kommunikationsnät.
    Fodor, Viktoria
    KTH, Skolan för elektro- och systemteknik (EES), Kommunikationsnät.
    Ascenso, J.
    Monteiro, P.
    Demo: Enabling image analysis tasks in visual sensor networks2014Inngår i: Proceedings of the 8th ACM/IEEE International Conference on Distributed Smart Cameras, ICDSC 2014, Association for Computing Machinery (ACM), 2014, s. a46-Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This demo showcases some of the results obtained by the GreenEyes project, whose main objective is to enable visual analysis on resource-constrained multimedia sensor networks. The demo features a multi-hop visual sensor network operated by BeagleBones Linux computers with IEEE 802.15.4 communication capabilities, and capable of recognizing and tracking objects according to two different visual paradigms. In the traditional compress-then-analyze (CTA) paradigm, JPEG compressed images are transmitted through the network from a camera node to a central controller, where the analysis takes place. In the alternative analyze-then-compress (ATC) paradigm, the camera node extracts and compresses local binary visual features from the acquired images (either locally or in a distributed fashion) and transmits them to the central controller, where they are used to perform object recognition/tracking. We show that, in a bandwidth constrained scenario, the latter paradigm allows to reach better results in terms of application frame rates, still ensuring excellent analysis performance.

  • 232.
    Barrera Diaz, Carlos Alberto
    et al.
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Oscarsson, Jan
    Högskolan i Skövde, Institutionen för ingenjörsvetenskap. Högskolan i Skövde, Forskningscentrum för Virtuella system.
    Lidberg, Simon
    Volvo Car Corporation, Skövde, Sweden.
    Sellgren, Tommy
    Volvo Car Corporation, Skövde, Sweden.
    A Study of Discrete Event Simulation Project Data and Provenance Information Management in an Automotive Manufacturing Plant2017Inngår i: Proceedings of the 2017 Winter Simulation Conference / [ed] W. K. V. Chan, A. D’Ambrogio, G. Zacharewicz, N. Mustafee, G. Wainer, E. Page, IEEE, 2017, , s. 12s. 4012-4023Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Discrete Event Simulation (DES) project data management is a complex and important engineering activity which impacts on an organization’s efficiency. This efficiency could be decreased by the lack of provenance information or the unreliability of existing information regarding previous simulation projects, all of which complicates the reusability of the existing data. This study presents an analysis of the management of simulation projects and their provenance data, according to the different types of scenarios usually found at a manufacturing plant. A survey based on simulation projects at an automotive manufacturing plant was conducted, in order to categorize the information regarding the studied projects, map the available provenance data and standardize its management. This study also introduces an approach that demonstrates how a structured framework based on the specific data involved in the different types of scenarios could allow an improvement of the management of DES projects.

  • 233.
    Bassoo, Vandana
    et al.
    Victoria University, Australia.
    Tom, K
    Victoria University, Australia.
    Mustafa, A. K.
    Victoria University, Australia.
    Cijvat, Ellie
    Lunds Universitet.
    Sjöland, Henrik
    Lunds Universitet.
    Faulkner, Mike
    Victoria University, Australia.
    Potential Architecture for Future Generation "Green" Wireless Base Station2009Inngår i: 2009 4th International Symposium on Wireless and Pervasive Computing, ISWPC 2009, IEEE, 2009, artikkel-id 4800602Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Current radio frequency power amplifiers (PAs) in 3G base stations have very high power consumption leading to a hefty cost and negative environmental impact. In this paper, we propose a potential architecture design for future wireless base station. Issues associated with components of the architecture are investigated. A comparison of PA with pulse width modulation drive and PA with envelope elimination and restoration (EER) drive is offered. EER-driven PA promises high efficiency over a wide dynamic range but has bandwidth expansion problems. A novel approach which reduces bandwidth expansion on the envelope by 54% is proposed. A modulator is used to convert amplitude and phase information into the edges of a pulse train. The modulator also eradicates some analog components present in traditional base station design.

  • 234.
    Bassoo, Vandana
    et al.
    Victoria University, Australia.
    Tom, Kevin
    Victoria University, Australia.
    Mustafa, A. K.
    Victoria University, Australia.
    Cijvat, Ellie
    Lund University.
    Sjöland, Henrik
    Lund University.
    Faulkner, Mike
    Victoria University; Australia.
    A potential transmitter architecture for future generation green wireless base station2009Inngår i: EURASIP Journal on Wireless Communications and Networking, ISSN 1687-1472, E-ISSN 1687-1499, artikkel-id 821846Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Current radio frequency power amplifiers in 3G base stations have very high power consumption leading to a hefty cost and negative environmental impact. In this paper, we propose a potential architecture design for future wireless base station. Issues associated with components of the architecture are investigated. The all-digital transmitter architecture uses a combination of envelope elimination and restoration (EER) and pulse width modulation (PWM)/pulse position modulation (PPM) modulation. The performance of this architecture is predicted from the measured output power and efficiency curves of a GaN amplifier. 57% efficiency is obtained for an OFDM signal limited to 8 dB peak to average power ratio. The PWM/PPM drive signal is generated using the improved Cartesian sigma delta techniques. It is shown that an RF oversampling by a factor of four meets the WLAN spectral mask, and WCDMA specification is met by an RF oversampling of sixteen.

  • 235.
    Bastani, Saeed
    et al.
    The University of Sydney.
    Landfeldt, Björn
    Lund University.
    Rohner, Christian
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Gunningberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    A social node model for realising information dissemination strategies in delay tolerant networks2012Inngår i: Proceedings of the 15th ACM international conference on Modeling, analysis and simulation of wireless and mobile systems, New york: ACM Press, 2012, s. 79-88Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In Delay Tolerant Networks (DTNs) as an emerging content dissemination platform, mobile nodes opportunistically exchange content as they meet, with the intent of disseminating content among nodes that share common interests. During a meeting, nodes can exchange both content of direct interest to themselves as well as content that is of interest to a larger set of nodes that may be encountered in the future. The utility of DTN is governed by the content exchange opportunity (the amount of content that can be exchanged during a meeting) as well as the selection of content to be exchanged in order to maximise the interest nodes will have in information they are exposed to. Considering that there is a cost associated with the content exchange (e.g. battery usage, buffer occupancy or consumed transmission opportunity) the aim for nodes participating in content dissemination should be to maximise their payoff. In this paper, we contribute a generic framework for describing the characteristics of content exchange among participating nodes in a network. We incorporate a distributed information popularity measurement and the pairwise interaction of nodes modelled as a bargaining problem. The outcome of this process is the fair split up of dwelling time as a network resource and the selection of which content objects to exchange in order to maximise the nodes’ payoff. The framework is generally intended to be used as a capstone for investigation of content dissemination properties and various content exchange strategies in a DTN, a topic addressed in this paper and experiments conducted to validate the function and correctness of the proposed framework. 

  • 236. Bauer, K.
    et al.
    Boreli, R.
    Carlsson, N.
    Chen, Z.
    Francillon, A.
    Freudiger, J.
    Friedman, A.
    Gambs, S.
    Haddadi, H.
    Hecker, A.
    Hui, P.
    Kaafar, M. -A
    Köpf, B.
    Mahanti, A.
    Önen, M.
    Papadimitratos, Panagiotis
    KTH, Skolan för elektro- och systemteknik (EES), Kommunikationsnät.
    Ries, S.
    Salamatian, K.
    Schneider, F.
    Shikfa, A.
    Shue, C.
    Strufe, T.
    Uhlig, S.
    Uzun, E.
    Xie, G.
    Welcome message from the PADE chairs2013Inngår i: Welcome message from the PADE chairs  (Editorial), IEEE Computer Society, 2013, s. lxi-lxiiKonferansepaper (Annet vitenskapelig)
  • 237.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Harper, B.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Judge, J.
    Location Aware Mobile Computing1997Inngår i: Proceedings of ICT '97, IEEE , 1997, s. 1319-1324Konferansepaper (Fagfellevurdert)
  • 238.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Smith, Mark T.
    Location Augmented Mobile Computing and Communication Systems1997Inngår i: Proc. Third Asia-Pacific Conference on Communications (APCC’97), 1997, s. 827-831Konferansepaper (Fagfellevurdert)
  • 239.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Smith, Mark T.
    Location Based Personal Mobile Computing and Communication1998Inngår i: Proceedings of 9th IEEE Workshop on Local and Metropolitan Area Networks, IEEE , 1998, s. 23-24Konferansepaper (Fagfellevurdert)
  • 240.
    Beadle, H.W.P.
    et al.
    Wollongong University.
    Maguire Jr., Gerald Q.
    KTH, Tidigare Institutioner, Teleinformatik.
    Smith, Mark T.
    Using location and environment awareness in mobile communications1997Inngår i: Proceedings of the International Conference on Information, Communications and Signal Processing, ICICS, IEEE , 1997, s. 1781-1785Konferansepaper (Fagfellevurdert)
    Abstract [en]

    We are investigating the use of badge based wearable computers to create highly mobile location and environment aware systems. When coupled to intelligent servers the badges provide an unparalleled platform for human centred information environments. This paper describes the architecture of the badge, its distributed computing environment, and presents initial results of application development trials conducted by a class of telecommunications students at KTH.

  • 241.
    Becker, Kalle
    KTH, Tidigare Institutioner, Teleinformatik.
    Calling your mailbox1998Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This paper presents how the company for whom this work was preformed should act to add an email reading feature to their platform. It also includes an evaluation of the usability of such a system (called Popeye).

    A field trial with Popeye was carried out, and also analyzed to understand both how users want to use this kind of service and also to evaluate speech technology in such applications.

    This paper also briefly describes the platform and why it is a good idea to use Microsoft Transaction Server (MTS) together with COM when building large systems in a Windows NT environment.

    Two different approaches to creation of this feature are discussed and the design of a COM interface was done. This interface will let voice mail vendors connect with the system and this will minimize the hardware that the telecom operators will have to buy and maintain.

    The solution I prefer is the one that means that the company has to build a complete new product. This solution will be harder to implement but I think that it will give the company the most benefits in the end. My conclusions can be read in chapter 5.

  • 242. Beckman, C.
    et al.
    Borg, J.
    Johansson, J.
    Tecsor, Irina
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Design Considerations for the EISCAT_3D Phased Array Antenna2014Inngår i: 8th European Conference on Antennas and Propagation, EuCAP 2014, IEEE , 2014, s. 1700-1704Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents a background and an overview of the initial design considerations for phased array antenna being designed for the New Generation multi-static, incoherent-scatter radar station - EISCAT-3D - in Northern Scandinavia. Its anticipated electrical, mechanical and environmental design requirements are given both by the physics as well as by the extreme climate in the subarctic region of northern Scandinavia.

  • 243.
    Beermann, Mikael
    KTH, Tidigare Institutioner, Teleinformatik.
    Implementation of the Mobile Floating Agent Technique1996Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The computer has undergone an explosive development since they first arrived. Today nearly everybody uses computers more or less frequently. The trend is now that everyone has a little computer connected to others in a network. The computing power has become more decentralized, and therefore the need for communication has increased. Another thing that has changed the pattern is that the computers has become so small that it is no longer any problem to move them as long as one does not care about the network support, but of course one would like to have both the mobility and the network support.

    In my master thesis project I have implemented and evaluated parts of a new approach for dealing with the problems with mobility. This approach is called the mobile floating agent technique, and was developed by George Y. Liu at Ericsson Radio Systems AB, Kista. The main idea behind this is to have floating agents in the network, i.e. software entities that are virtually floating around in the network, arranging files and resources for the mobile user so that he can connect to a server in his neighbourhood, instead of connecting to his own server far away.

    I have implemented a simple file system testbed that uses the floating agent technique for caching purposes. There are two reasons for doing this implementation. The reason is for evaluation of the caching features, and the second reason is to have a platform to implement more advanced agent functions on.

    The design of the system has been done in an object oriented style, and the implementation has been done in C++.The system consists of two parts. One part is the client software, which has been implemented in another project, but modified by me, and runs on aPC with the Windows95 OS. The other part is the network part of the system, i.e. the part of the system that is not running in the client, is made for running on an UNIX station. The network part of the system consists of two parts itself. There are mobile floating agent managers, that manages the whole system, and agents, that serves the mobile clients, and communicates with both the client software and the mobile floating agent managers.

    In the evaluation part of the project I have compared the delay acquired when accessing a file in a remote network with and without an agent. I finally came to the conclusion that the gain won with the use of caches in the agents is maybe not as large that one should use caching as the primary object of the agents.

  • 244.
    Beermann, Mikael
    KTH, Tidigare Institutioner, Teleinformatik.
    Implementation of the Mobile Floating Agent Technique1996Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The computer has undergone an explosive development since they first arrived. Today nearly everybody uses computers more or less frequently. The trend is now that everyone has a little computer connected to others in a network. The computing power has become more decentralized, and therefore the need for communication has increased. Another thing that has changed the pattern is that the computers has become so small that it is no longer any problem to move them as long as one does not care about the network support, but of course one would like to have both the mobility and the network support.

    In my master thesis project I have implemented and evaluated parts of a new approach for dealing with the problems with mobility. This approach is called the mobile floating agent technique, and was developed by George Y. Liu at Ericsson Radio Systems AB, Kista. The main idea behind this is to have floating agents in the network, i.e. software entities that are virtually floating around in the network, arranging files and resources for the mobile user so that he can connect to a server in his neighbourhood, instead of connecting to his own server far away.  I have implemented a simple file system testbed that uses the floating agent technique for caching purposes. There are two reasons for doing this implementation. The reason is for evaluation of the caching features, and the second reason is to have a platform to implement more advanced agent functions on.

    The design of the system has been done in an object oriented style, and the implementation has been done in C++.The system consists of two parts. One part is the client software, which has been implemented in another project, but modified by me, and runs on aPC with the Windows95 OS. The other part is the network part of the system, i.e. the part of the system that is not running in the client, is made for running on an UNIX station. The network part of the system consists of two parts itself. There are mobile floating agent managers, that manages the whole system, and agents, that serves the mobile clients, and communicates with both the client software and the mobile floating agent managers.

    In the evaluation part of the project I have compared the delay acquired when accessing a file in a remote network with and without an agent. I finally came to the conclusion that the gain won with the use of caches in the agents is maybe not as large that one should use caching as the primary object of the agents.

  • 245. Behrooz, Alireza
    et al.
    Devlic, Alisa
    A Context-Aware Privacy Policy Language for Controlling Access to Context Information of Mobile Users2012Inngår i: Security and Privacy in Mobile Information and Communication Systems: Third International ICST Conference, MobiSec 2011, Aalborg, Denmark, May 17-19, 2011, Revised Selected Papers, Springer Berlin Heidelberg, 2012, s. 25-39Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper introduces a Context-aware Privacy Policy Language (CPPL) that enables mobile users to control who can access their context information, at what detail, and in which situation by specifying their context-aware privacy rules. Context-aware privacy rules map a set of privacy rules to one or more user's situations, in which these rules are valid. Each time a user's situation changes, a list of valid rules is updated, leaving only a subset of the specified rules to be evaluated by a privacy framework upon arrival of a context query. In the existing context-dependent privacy policy languages a user's context is used as an additional condition parameter in a privacy rule, thus all the specified privacy rules have to be evaluated when a request to access a user's context arrives. Keeping the number of rules that need to be evaluated small is important because evaluation of a large number of privacy rules can potentially increase the response time to a context query. CPPL also enables rules to be defined based on a user's social relationship with a context requestor, which reduces the number of rules that need to be defined by a user and that consequently need to be evaluated by a privacy mechanism. This paper shows that when compared to the existing context-dependent privacy policy languages, this number of rules (that are encoded using CPPL) decreases with an increasing number of user-defined situations and requestors that are represented by a small number of social relationship groups.

  • 246.
    Bektesevic, Edin
    KTH, Tidigare Institutioner, Teleinformatik.
    Embedded Linux for Purposes of Internet Appliances: (a.k.a. ‘The Wanderer Project’)1999Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    As the Internet continues to grow, now new Internet appliances are being marketed. At the same time, Linux is gradually becoming a competitive choice for desktop, server and embedded applications. How do these two facts relate to each other? What should be the position of Linux in Internet appliances, and how interesting is Linux? Where are the Internet appliances really positioned in terms of their needs for an operating system? How is Linux implemented in embedded applications?

    These are just some of the questions posed during this MSc. Project that this report aims to answer. In addition, we will examine how Linux is used in embedded applications and what it provides in terms of achieving their goals. Also, we will take a look at the compression methods that can be used for system size reduction and analyze their costs.

    The report will show that Linux is a competitive alternative for devices like WebPAD, that it leaves space for further time and cost efficient improvements, and that Internet appliances can get most of the benefits of Linux during its further evolution relatively cheaply.

  • 247.
    Bellagamba, Elisa
    et al.
    Ericsson Research.
    Andersson, Loa
    Ericsson AB.
    Sköldström, Pontus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS, Network Systems Laboratory (NS Lab).
    Ward, Dave
    Drake, John
    Configuration of Pro-Active Operations, Administration, and Maintenance (OAM) Functions for MPLS-based Transport Networks using LSP Ping2013Annet (Annet (populærvitenskap, debatt, mm))
  • 248. Bellagamba, Elisa
    et al.
    Kempf, James
    Sköldström, Pontus
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster (Stängd 20120101), Telekommunikationssystem, TSLab (stängd 2012-01-01).
    Link Failure Detection and Traffic Redirection in an Openflow Network2010Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    Failure detection and traffic redirection are implemented in an OpenFlow switch. Link failure detection packets, such as Bidirectional Forwarding Detection (BFD) packets, are periodically sent out on links to peer OpenFlow switches, such as via the Multi-protocol Label Switching (MPLS) Transport Profile (MPLS-TP). Link failure detection packets are received from the peer OpenFlow switches on the links, and monitored. A link failure is detected if no incoming link failure detection packets are received on a link for a predetermined interval. In the event of a link failure, traffic is redirected from the failed link to a backup link by altering entries on a flow table of the OpenFlow switch.

  • 249.
    Bellalta, Boris
    et al.
    Universitat Pompeu Fabra, Barcelona, Spain.
    Barcelo, Jaume
    Universidad Carlos III, Madrid, Spain.
    Staehle, Dirk
    University of Wurzburg, Wurzburg, Germany.
    Vinel, Alexey
    Department of Communications Engineering, Tampere University of Technology, Tampere, Finland.
    Oliver, Miquel
    Universitat Pompeu Fabra, Barcelona, Spain.
    On the performance of packet aggregation in IEEE 802.11ac MU-MIMO WLANs2012Inngår i: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 16, nr 10, s. 1588-1591Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Multi-user spatial multiplexing combined with packet aggregation can significantly increase the performance of Wireless Local Area Networks (WLANs). In this letter, we present and evaluate a simple technique to perform packet aggregation in IEEE 802.11ac MU-MIMO (Multi-user Multiple Input Multiple Output) WLANs. Results show that in non-saturation conditions both the number of active stations (STAs) and the queue size have a significant impact on the system performance. If the number of STAs is excessively high, the heterogeneity of destinations in the packets contained in the queue makes it difficult to take full advantage of packet aggregation. This effect can be alleviated by increasing the queue size, which increases the chances of scheduling a large number of packets at each transmission, hence improving the system throughput at the cost of a higher delay. © 1997-2012 IEEE.

  • 250.
    Bellalta, Boris
    et al.
    Universitat Pompeu Fabra, Barcelona, Spain.
    Belyaev, Evgeny
    Tampere University of Technology, Finland.
    Jonsson, Magnus
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Vinel, Alexey
    Högskolan i Halmstad, Akademin för informationsteknologi, Halmstad Embedded and Intelligent Systems Research (EIS), Centrum för forskning om inbyggda system (CERES).
    Performance evaluation of IEEE 802.11p-enabled vehicular video surveillance system2014Inngår i: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 18, nr 4, s. 708-711Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Prospective IEEE 802.11p-based vehicular surveillance system, where video from the vehicle on-board camera is transmitted to the management center, is considered. Multi-hop transmission from the vehicle to the nearest roadside unit and then-via other roadside units-to the gateway is addressed. In this letter we assess the feasibility of such system by analyzing the video end-to-end distortion for a target vehicle, located several hops away from the gateway, when it is alone or there are also other vehicles transmitting video. We demonstrate the importance of dynamic adaptation of the video bit rate of each vehicle depending on the number and positions of the participating vehicles. © 2014 IEEE.

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