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  • 851.
    Walan, Susanne
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Mellanstadieelevers syn på naturvetenskap som en del av vardagen utanför skolan2014In: FND 2014, Karlstad, 5-6 november, 2014., 2014Conference paper (Refereed)
  • 852.
    Walan, Susanne
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Star Wars Irl2017Conference paper (Other (popular science, discussion, etc.))
    Abstract [sv]

    Rymdmusik, finns det? Finns det ljud i rymden överhuvudtaget? Rymdfilmer, vad är sant och vad är falskt? Vilken roll spelar musiken i rymdfilmerna? Vi kombinerar fantastiska IRL rymdbilder med spännande musik.

  • 853.
    Walan, Susanne
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Upplysande naturvetenskapligt lärande2015Other (Other (popular science, discussion, etc.))
  • 854.
    Walan, Susanne
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Chang Rundgren, Shu-Nu
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
    Student responses to a context- and inquiry-based three-step teaching model2015In: Teaching science, ISSN 1449-6313, Vol. 61, no 2, p. 33-39Article in journal (Refereed)
    Abstract [en]

    Research has indicated that both context- and inquiry-based approaches could increase student interest in learning sciences. This case study aims to present a context- and inquiry-based combined teaching approach, using a three-step teaching model developed by the PROFILES project, and investigates Swedish students' responses to the activity. A Likert scale questionnaire was used for the data collection. The results of a total of 105 15-year-old students showed that, overall, the students were highly positive about this science teaching module.

  • 855.
    Walan, Susanne
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Mc Ewen, Birgitta
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Health Sciences.
    Gericke, Niklas
    Karlstad University, Faculty of Social and Life Sciences.
    Enhancing primary science: An exploration of teachers' own ideas of solutions to challenges in inquiry- and context-based teaching2016In: Education 3-13, ISSN 0300-4279, E-ISSN 1475-7575, Vol. 44, no 1, p. 81-92Article in journal (Refereed)
    Abstract [en]

    Studies of inquiry- and context-based science education (IC-BaSE) have shown that teachers find these approaches problematic. In this study, 12 primary school teachers’ reflections on challenges related to IC-BaSE are explored. The aim of the study was to investigate which challenges primary teachers experience when working with IC-BaSE and how these may be solved. Group discussions and individual portfolios were used for data collection. Content analysis showed that the challenges teachers experienced were mainly practical relating to: how to find contexts, lack of time, handling big classes, students working at different paces, handling materials, and the teachers' need of control. The teachers also presented their own ideas of solutions to the challenges.

  • 856. Weber, Stefan G.
    et al.
    Martucci, Leonardo
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Ries, Sebastian
    Mühlhäuser, Max
    Technische Universität Darmstadt.
    Towards trustworthy identity and access management for the future internet2010In: Proceedings of the 4th International Workshop on Trustworthy Internet ofPeople, Things & Services (Trustworthy IoPTS 2010), 2010Conference paper (Refereed)
    Abstract [en]

    The Future Internet, in its different variants, promises a global connectivity of people, things and services.However, in order to develop its full potential and to achieve an accepted, seamless integration of Internet use into daily lives, severe security issues have to be addressed. In this paper, we propose to establish security and trustworthiness by means of an integrated identity and access management. Especially, we sketch the foundations of a novel identity and access management approach that is tailored for the Future Internet. We provide mechanisms for flexible modeling and description of digital user identities with support to transaction-based privacy protection, access to personal data, flexible third party accountability and end-to-end secure communication. The mechanisms are tailored for the use on a trusted personaldevice called Minimal Entity, which provides a trustworthy gateway to benefit from the offerings of the Future Internet.

  • 857.
    Weinrank, Felix
    et al.
    Münster University of Applied Sciences.
    Grinnemo, Karl-Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Bozakov, Zdravko
    Dell EMC Research Europe.
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Dreibholz, Thomas
    Simula Research Laboratory.
    Fairhurst, Gorry
    University of Aberdeen.
    Hurtig, Per
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Khademi, Naeem
    University of Oslo.
    Tüxen, Michael
    Münster University of Applied Sciences.
    A NEAT Way to Browse the Web2017In: Applied Networking Research Workshop (ANRW) 2017, Prague, Czech Republic, July 15, 2017., Thomas Dreibholz , 2017Conference paper (Refereed)
    Abstract [en]

    There is a growing concern that the Internet transport layer has become ossified in the face of emerging novel applications, and that further evolution has become very difficult. The NEAT system is a novel and evolvable transport system that decouples applications from the underlying transport layer and network services. In so doing, it facilitates dynamic transport selection. This demo shows how the NEAT system is able to dynamically select the most appropriate transport solution for the Mozilla Firefox web browser.

  • 858.
    Westlinder, Simon
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Video Traffic Classification: A Machine Learning approach with Packet Based Features using Support Vector Machine2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Internet traffic classification is an important field which several stakeholders are dependent on for a number of different reasons. Internet Service Providers (ISPs) and network operators benefit from knowing what type of traffic that propagates over their network in order to correctly treat different applications. Today Deep Packet Inspection (DPI) and port based classification are two of the more commonly used methods in order to classify Internet traffic. However, both of these techniques fail when the traffic is encrypted. This study explores a third method, classifying Internet traffic by machine learning in which the classification is realized by looking at Internet traffic flow characteristics instead of actual payloads. Machine learning can solve the inherent limitations that DPI and port based classification suffers from. In this study the Internet traffic is divided into two classes of interest: Video and Other. There exist several machine learning methods for classification, and this study focuses on Support Vector Machine (SVM) to classify traffic. Several traffic characteristics are extracted, such as individual payload sizes and the longest consecutive run of payload packets in the downward direction. Several experiments using different approaches are conducted and the achieved results show that overall accuracies above 90% are achievable.

  • 859.
    Wiklund, Kristian
    et al.
    Ericsson AB, SE-16480 Kista, Sweden.;Malardalen Univ, Sch Innovat Design & Engn, Vasteras, Sweden..
    Sundmark, Daniel
    Malardalen Univ, Sch Innovat Design & Engn, Vasteras, Sweden..
    Eldh, Sigrid
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Ericsson AB, SE-16480 Kista, Sweden.;Karlstad Univ, Karlstad, Sweden..
    Lundqvist, Kristina
    Malardalen Univ, Sch Innovat Design & Engn, Vasteras, Sweden..
    Impediments for Automated Testing - An Empirical Analysis of a User Support Discussion Board2014In: 2014 IEEE Seventh International Conference on Software Testing, Verification and Validation, IEEE, 2014, p. 113-122Conference paper (Refereed)
    Abstract [en]

    To better understand the challenges encountered by users and developers of automatic software testing, we have performed an empirical investigation of a discussion board used for support of a test automation framework having several hundred users. The messages on the discussion board were stratified into problem reports, help requests, development information, and feature requests. The messages in the problem report and help request strata were then sampled and analyzed using thematic analysis, searching for common patterns. Our analysis indicate that a large part of the impediments discussed on the board are related to issues related to the centralized IT environment, and to erroneous behavior connected to the use of the framework and related components. We also observed a large amount of impediments related to the use of software development tools. Turning to the help requests, we found that the majority of the help requests were about designing test scripts and not about the areas that appear to be most problematic. From our results and previous publications, we see a clear need to simplify the use, installation, and configuration of test systems of this type. The problems attributable to software development tools suggest that testers implementing test automation need more skills in handling those tools, than historically has been assumed. Finally, we propose that further research into the benefits of centralization of tools and IT environments, as well as structured deployment and efficient use of test automation, is performed.

  • 860.
    Wiktor Wlodarczyk, Tomasz
    et al.
    University of Stavanger.
    Pais, Rui
    University of Stavanger.
    Azraoui, Monir
    EURECOM.
    Önen, Melek
    EURECOM.
    Reuben, Jenni
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science. Karlstad University.
    Pulls, Tobias
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Sellami, Mohamed
    ARMINES EMN.
    Royer, Jean-Claude
    ARMINES EMN.
    Felici, Massimo
    HP Labs.
    Bernsmed, Karin
    SINTEF.
    Rübsamen, Thomas (Editor)
    Hochschule Furtwangen University.
    D:C-8.3 Automation Service for the Framework of Evidence2015Report (Refereed)
  • 861.
    Willemse, Isabella
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Matematiksvårigheter i skolan: en studie i en sydafrikansk kåkstad2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 862.
    Winberg, André
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Golrang, Ramin Alberto
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Analytics as a Service: Analysis of services in Microsoft Azure2017Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 863.
    Winter, Philipp
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Enhancing Censorship Resistance in the Tor Anonymity Network2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Baksidestext

    The Tor network was originally designed as low-latency anonymity network.However, as the years progressed, Tor earned a reputation as also being a useful tool to circumvent Internet censorship. At times, the network counted 30,000 users only from China. Censors reacted by tightening their grip on the national communication infrastructure. In particular, they developed techniques to prevent people from being able to access the Tor network. This arms race now counts several iterations and no end is in sight.

    This thesis contributes to a censorship-resistant Tor network in two ways. First, it analyses how existing censorship systems work. In particular, the Great Firewall of China is analysed in order to obtain an understanding of its capabilities as well as to explore circumvention opportunities. Second, this thesis proposes practical countermeasures to circumvent Internet censorship. In particular, it presents a novel network protocol which is resistant to the Great Firewall's active probing attacks.

  • 864.
    Winter, Philipp
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Measuring and circumventing Internet censorship2014Doctoral thesis, monograph (Other academic)
    Abstract [en]

    An ever increasing amount of governments, organisations, and companies employ Internet censorship in order to filter the free flow of information.  These efforts are supported by an equally increasing number of companies focusing on the development of filtering equipment.

    Only what these entities consider right can pass the filters. This practice constitutes a violation of the Universal Declaration of Human Rights and hampers progress.  This thesis contributes novel techniques to measure and to circumvent Internet censorship. In particular, we 1) analyse how the Great Firewall of China is blocking the Tor network by using active probing techniques as well as side channel measurements, we

    2) propose a concept to involve users in the process of censorship analysis, we 3) discuss the aptitude of a globally-deployed network measurement platform for censorship analysis, and we 4) propose a novel circumvention protocol. We attach particular importance to practicality and usability. Most of the techniques proposed in this thesis were implemented and some of them are deployed and used on a daily basis.  We demonstrate that the measurement techniques proposed in this thesis are practical and useful by applying them in order to shed light on previously undocumented cases of Internet censorship. We employed our techniques in three countries and were able to expose previously unknown censorship techniques and cooperation between a corporation and a government for the sake of censorship. We also implemented a circumvention protocol which was subsequently deployed and is used to evade the Great Firewall of China.

  • 865.
    Winter, Philipp
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Towards a Censorship Analyser for Tor2013Conference paper (Refereed)
    Abstract [en]

    Analysing censorship incidents targeting popular circumvention tools such as Tor can be a tedious task. Access to censoring networks is typically difficult to obtainand remote analysis is not always possible. Analysis is however feasible if users behind the censoring networks are given the opportunity to help. In this paper, we propose a lightweight censorship analyser for Tor which is meant to be run by volunteering users. The analyser automatically gathers relevant data and the final report is sent back to the Tor developers. Our design builds on existing software and should be easy to bundle and deploy.

  • 866.
    Winter, Philipp
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Crandall, Jedidiah R.
    The Great Firewall of China: How it Blocks Tor and Why it is Hard to Pinpoint2012In: Login: The Usenix Magazine, ISSN 1044-6397, E-ISSN 2169-9364, ISSN 1044-6397, Vol. 37, no 6, p. 42-50Article in journal (Other academic)
  • 867.
    Winter, Philipp
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science. Princeton University.
    Ensafi, Roya
    Princeton University.
    Loesing, Karsten
    The Tor Project.
    Feamster, Nick
    Princeton University.
    Identifying and characterizing Sybils in the Tor network2016In: Proceedings of the 25th USENIX Security Symposium, USENIX - The Advanced Computing Systems Association, 2016, p. 1169-1185Conference paper (Refereed)
    Abstract [en]

    Being a volunteer-run, distributed anonymity network, Tor is vulnerable to Sybil attacks. Little is known about real-world Sybils in the Tor network, and we lack practical tools and methods to expose Sybil attacks. In this work, we develop sybilhunter, a system for detecting Sybil relays based on their appearance, such as configuration; and behavior, such as uptime sequences. We used sybilhunter’s diverse analysis techniques to analyze nine years of archived Tor network data, providing us with new insights into the operation of real-world attackers. Our findings include diverse Sybils, ranging from botnets, to academic research, and relays that hijacked Bitcoin transactions. Our work shows that existing Sybil defenses do not apply to Tor, it delivers insights into realworld attacks, and provides practical tools to uncover and characterize Sybils, making the network safer for its users.

  • 868.
    Winter, Philipp
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Koewer, Richard
    FH Campus Wien, Austria.
    Mulazzani, Martin
    SBA Research, Austria.
    Huber, Markus
    SBA Research, Austria.
    Schrittwieser, Sebastian
    SBA Research, Austria.
    Lindskog, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Weippl, Edgar
    SBA Research, Austria.
    Spoiled Onions: Exposing Malicious Tor Exit Relays2014In: Privacy Enhancing Technologies, Springer, 2014, p. 304-331Conference paper (Refereed)
    Abstract [en]

    Tor exit relays are operated by volunteers and together push more than 1 GiB/s of network traffic. By design, these volunteers are able to inspect and modify the anonymized network traffic. In this paper, we seek to expose such malicious exit relays and document their actions. First, we monitored the Tor network after developing two fast and modular exit relay scanners-one for credential sniffing and one for active MitM attacks. We implemented several scanning modules for detecting common attacks and used them to probe all exit relays over a period of several months. We discovered numerous malicious exit relays engaging in a multitude of different attacks. To reduce the attack surface users are exposed to, we patched Torbutton, an existing browser extension and part of the Tor Browser Bundle, to fetch and compare suspicious X. 509 certificates over independent Tor circuits. Our work makes it possible to continuously and systematically monitor Tor exit relays. We are able to detect and thwart many man-in-the-middle attacks, thereby making the network safer for its users. All our source code is available under a free license.

  • 869.
    Winter, Philipp
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Lindskog, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Spoiled Onions: Exposing Malicious Tor Exit Relays2014Report (Other academic)
    Abstract [en]

    Several hundred Tor exit relays together push more than 1 GiB/s of network traffic. However, it iseasy for exit relays to snoop and tamper with anonymised network traffic and as all relays are runby independent volunteers, not all of them are innocuous.

    In this paper, we seek to expose malicious exit relays and document their actions. First, wemonitored the Tor network after developing a fast and modular exit relay scanner. We implementedseveral scanning modules for detecting common attacks and used them to probe all exit relays over aperiod of four months. We discovered numerous malicious exit relays engaging in different attacks.To reduce the attack surface users are exposed to, we further discuss the design and implementationof a browser extension patch which fetches and compares suspicious X.509 certificates overindependent Tor circuits.

    Our work makes it possible to continuously monitor Tor exit relays. We are able to detect andthwart many man-in-the-middle attacks which makes the network safer for its users. All our code isavailable under a free license.

  • 870.
    Winter, Philipp
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Pulls, Tobias
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Fuss, Juergen
    Upper Austria University of Applied Sciences.
    ScrambleSuit: A Polymorphic Network Protocol to Circumvent Censorship2013Conference paper (Refereed)
    Abstract [en]

    Deep packet inspection technology became a cornerstone of Internet censorship by facilitating cheap and effective filtering of what censors consider undesired information. Moreover, filtering is not limited to simple pattern matching but makes use of sophisticated techniques such as active probing and protocol classification to block access to popular circumvention tools such as Tor. In this paper, we propose ScrambleSuit; a thin protocol layer above TCP whose purpose is to obfuscate the transported application data. By using morphing techniques and a secret exchanged out-of-band, we show that ScrambleSuit can defend against active probing and other fingerprinting techniques such as protocol classification and regular expressions. We finally demonstrate that our prototype exhibits little overhead and enables effective and lightweight obfuscation for application layer protocols.

  • 871.
    Winter, Philipp
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Pulls, Tobias
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Fuss, Juergen
    Upper Austria University of Applied Sciences.
    ScrambleSuit: A Polymorphic Network Protocol to Circumvent Censorship2013Report (Other academic)
    Abstract [en]

    Deep packet inspection technology became a cornerstone of Internet censorship by facilitating cheap and effective filtering of what censors consider undesired information. Moreover, filtering is not limited to simple pattern matching but makes use of sophisticated techniques such as active probing and protocol classification to block access to popular circumvention tools such as Tor.

    In this paper, we propose ScrambleSuit; a thin protocol layer above TCP whose purpose is to obfuscate the transported application data. By using morphing techniques and a secret exchanged out-of-band, we show that ScrambleSuit can defend against active probing and other fingerprinting techniques such as protocol classification and regular expressions.

    We finally demonstrate that our prototype exhibits little overhead and enables effective and lightweight obfuscation for application layer protocols.

  • 872.
    Wästlund, Erik
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Psychology. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT. Karlstad University, Faculty of Economic Sciences, Communication and IT, Service Research Center.
    Fischer Hübner, Simone
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Graf, Conny
    Hochleitner, Christina
    Wolkerstorfer, Peter
    Angulo, Julio
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Final HCI Research Report: Deliverable D4.1.52011Report (Refereed)
    Abstract [en]

    This deliverable provides an overview of recent research results of Activity 4 ‘Usability’ of PrimeLife, where an emphasis is put on those results, which have not been reported in the same detail in other HCI-related PrimeLife deliverables yet. The first part reports about our results in the area of User Interface (UI) Representation of Privacyenhancing Identity Management Concepts and presents research on PET methodologies, mental models for anonymous credentials and the results from the final round of end-user evaluations of the UI prototypes developed during the PrimeLife project. The second part reports about our work in the area of usable privacy policies and presents the final results of Activity 4’s research on policy icons and on a user-friendly management and display of PPL (PrimeLife Policy Language) policies.

  • 873.
    Xiang, Zhengzhe
    et al.
    Zhejiang University, Peoples Republic of China.
    Deng, Shuiguang
    Zhejiang University, Peoples Republic of China.
    Taheri, Javid
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Zomaya, Albert
    University of Sydney, Australia.
    Dynamical Service Deployment and Replacement in Resource-Constrained Edges2019In: Mobile Networks and Applications , ISSN 1383-469X, E-ISSN 1572-8153Article in journal (Refereed)
    Abstract [en]

    With the rapid development of mobile computing technology, more and more complex tasks are now able to be fulfilled on users’ mobile devices with an increasing number of novel services. However, the development of mobile computing is limited by the latency brought by unstable wireless network and the computation failure caused by the constrained resources of mobile devices. Therefore, people turn to establish a service provisioning system based on mobile edge computing (MEC) model to solve this problem. With the help of services deployed on edge servers, the latency can be reduced and the computation can be offloaded. Though the edge servers have more available resources than mobile devices, they are still resource-constrained, so they must carefully choose the services for deployment. In this paper, we focus on improving performance of the service provisioning system by deploying and replacing services on edge servers. Firstly, we design and implement a prototype of service provisioning system that simulates the behaviors between users and servers. Secondly, we propose an approach to deploy services on edge servers before the launching of these servers, and propose an approach to replace services on edge servers dynamically. Finally, we conduct a series of experiments to evaluate the performance of our approaches. The result shows that our approach can improve the performance of service provisioning systems.

  • 874.
    Yedugundla, Kiran
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Evaluating and Reducing Multipath Transport Latency2019Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Access to the Internet is a very significant part of everyday life with increasing online services such as news delivery, banking, gaming, audio and high quality movies. Applications require different transport guarantees with some requiring higher bandwidth and others low latency. Upgrading access link capacity does not guarantee faster access to the Internet as it offers higher bandwidth but may not offer low latency. With increasing number of mobile devices supporting more than one access technologies (e.g., WLAN, 3G, 4G,..), there is a need to analyse the impact of using multiple such technologies at the same time. Legacy transport protocols such as TCP or SCTP are only able to connect to one access network at a time to create an end-to-end connection. When more than one access technology is used, there may be a large difference in the data rate offered by each technology. This asymmetry might impact latency sensitive applications by creating out of order delivery. In this thesis, we focus on the latency aspect of multipath transport protocol performance. We consider CMT-SCTP and Multipath TCP as available multipath protocols that were designed for exploiting multiple paths for better throughput and reliability. We consider various real world traffic scenarios such as Video, Gaming and Web traffic to measure end-to-end latency. We perform simulations, emulations and experiments using heterogeneous network settings involving access networks with different bandwidth, delay and loss characteristics. MPTCP performs better in terms of latency than CMT-SCTP and TCP in certain scenarios where available paths are symmetric. However, MPTCP does not perform well in asymmetric scenarios with latency sensitive traffic. This analysis provides insights in to various areas of improvement in MPTCP such as scheduling and loss recovery to achieve low latency. We further focus on packet loss recovery in MPTCP for specific cases of tail losses to reduce latency. Tail losses are the losses that occur at the end of a packet stream. Recovering such losses is of higher significance to latency sensitive applications. We propose a modification to the use of TLP, a mechanism in TCP for tail loss recovery. We evaluate the performance of proposed TLP modification, first using emulations and with real world network experiments. Our results show significant improvements in latency for specific loss scenarios in emulations and up to 50% improvement in experiments.

  • 875.
    Yedugundla, Kiran
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Hurtig, Per
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Handling Packet Losses in Cloud-Based Application Traffic2019In: Proceedings of the 9th International Conference on Cloud Computing and Services Science - Volume 1: CLOSER, SciTePress, 2019, p. 111-119Conference paper (Refereed)
    Abstract [en]

    Internet traffic is comprised of data flows from various applications with unique traffic characteristics. For many cloud applications, end-to-end latency is a primary factor affecting the perceived user experience. As packet losses cause delays in the communication they impact user experience, making efficient handling of packet losses an important function of transport layer protocols. Multipath TCP (MPTCP) is a modification to TCP that enables simultaneous use of several paths for a TCP flow. MPTCP is known to improve throughput. However, the performance of MPTCP is not optimal when handling certain loss scenarios. Efficient packet loss recovery is thus important to achieve desirable flow completion times for interactive cloud-based applications. In this paper we evaluate the performance of MPTCP in handling tail losses using traffic traces from various cloud-based applications. Tail losses, losses that occur at the end of a flow or traffic burst, are particularly challenging from a latency perspective as they are difficult to detect and recover in a timely manner. Tail losses in TCP are handled by using a tail loss probe (TLP) mechanism which was adapted to MPTCP from TCP. We investigate the performance of TLP in MPTCP, comparing the standard implementation to a recently proposed, less conservative approach. Our experimental results show that a less conservative implementation of TLP performs significantly better than the standard implementation in handling tail losses, reducing the average burst completion time of cloud based applications when tail loss occurs by up to 50% in certain cases.

  • 876.
    Yedugundla, Kiran
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Hurtig, Per
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Multipath TCP: Can it Reduce Transport Latency for Web Traffic?2015Conference paper (Refereed)
  • 877.
    Yedugundla, Kiran
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Hurtig, Per
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Brunström, Anna
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Probe or Wait: Handling tail losses using Multipath TCP2017In: 2017 IFIP Networking Conference (IFIP Networking) and Workshops, IEEE, 2017Conference paper (Refereed)
    Abstract [en]

    Packet losses are known to affect the performance of latency sensitive Internet applications such as media streaming and gaming. Transport protocols recover from packet loss in order to provide reliable end-to-end communication and improve user experience. The efficiency of loss recovery mechanisms influences the completion time of flows, and thus also the application performance as perceived by the end user. In this paper we focus on state-of-the-art loss recovery mechanisms for TCP and Multipath TCP. We use controlled tail loss scenarios to evaluate the performance of loss recovery mechanisms and, based on the observations, we propose an enhanced tail loss recovery mechanism for Multipath TCP, to improve the loss recovery time. Our experiment results, using the Linux Multipath TCP implementation, show consistent end-to-end latency performance improvement in considered scenarios.

  • 878.
    Yedugundla, Venkata Kiran
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Ferlin, Simone
    Simula Research Laboratory, Oslo, Norway.
    Dreibholz, Thomas
    Simula Research Laboratory, Oslo, Norway.
    Alay, Özgü
    Simula Research Laboratory, Oslo, Norway.
    Kuhn, Nicolas
    IMT Télécom Bretagne, IRISA, Cesson-Sévigné, France.
    Hurtig, Per
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Brunstrom, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Is Multi-Path Transport Suitable for Latency Sensitive Traffic?2016In: Computer Networks, ISSN 1389-1286, E-ISSN 1872-7069, Vol. 105, p. 1-21Article in journal (Refereed)
    Abstract [en]

    This paper assesses whether multi-path communication can help latency-sensitive applications to satisfy the requirements of their users. We consider Concurrent Multi-path Transfer for SCTP (CMT-SCTP) and Multi-path TCP (MPTCP) and evaluate their proficiency in transporting video, gaming, and web traffic over combinations of WLAN and 3G interfaces. To ensure the validity of our evaluation, several experimental approaches were used including simulation, emulation and live experiments. When paths are symmetric in terms of capacity, delay and loss rate, we find that the experienced latency is significantly reduced, compared to using a single path. Using multiple asymmetric paths does not affect latency - applications do not experience any increase or decrease, but might benefit from other advantages of multi-path communication. In the light of our conclusions, multi-path transport is suitable for latency-sensitive traffic and mature enough to be widely deployed. 

  • 879.
    Zeljkovic, Ensar
    et al.
    Univ Antwerp, Belgium.
    Marquez-Barja, Johann M.
    Univ Antwerp, Belgium.
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Riggio, Roberto
    FBK CREATE, NET, Italy.
    Latre, Steven
    Univ Antwerp, Belgium.
    Proactive Access Point Driven Handovers in IEEE 802.11 Networks2018In: 14th International Conference on Network and Service Management, CNSM 2018 / [ed] S. Salsano, R. Riggio, T. Ahmed, T. Samak, CRP. DosSantos, IEEE, 2018, p. 261-267Conference paper (Refereed)
    Abstract [en]

    In large and densely deployed IEEE 802.11 networks, a fast and seamless handover scheme is an important aspect in order to provide reliable connectivity for mobile users. However, IEEE 802.11 only supports decentralized, reactive and mobile node-driven handovers resulting in long handover times, packet loss due to interrupted connectivity and sub-optimal access point selection. Recently, centralized approaches have been developed that try to solve many of the challenges but these are mostly proprietary, reactive and require changes to mobile node stacks. In this paper, we propose a novel handover solution based on the principle of Software Defined Networking, that addresses the aforementioned challenges. Using virtualization and softwarization, we shift the traditional mobile node-driven handovers to the access point, while maintaining compliance with legacy devices. Moreover, we develop a proactive handover algorithm ADNA, which combines network state, traffic load and node mobility information. We evaluate our approach extensively in a testbed, showing that it outperforms existing approaches by improving the overall throughput by 116% while reducing the number of handovers by 44% on average.

  • 880.
    Zhang, Ge
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Counteract DNS Attacks on SIP Proxies Using Bloom Filters2013In: 2013 International Conference on Availability, Reliability and Security, IEEE, 2013, p. 678-684Conference paper (Refereed)
    Abstract [en]

    SIP proxies play an important part in VoIP services. A Denial of Service (DoS) attack on them may cause the failure of the whole network. We investigate such a DoS attack by exploiting DNS queries. A SIP proxy needs to resolve domain names for processing a message. However, a DNS resolution may take a while. To avoid being blocked, a proxy suspends the processing task of the current message during its name resolution, so that it can continue to deal with other messages. Later when the answer is received, the suspended task will be resumed. It is an asynchronous implementation of DNS queries. Unfortunately, this implementation consumes memory storage and also brings troubles like a race condition. An attacker can collect a list of domain names which take seconds to resolve. Then, the attacker sends to a victim SIP proxy messages which contain these domain names. As a result, the victim proxy has to suspend a number of messages in a short while. Our experiments show that a SIP proxy can be easily crashed by such an attack and thus be not available anymore. To solve the problem, we analyzed the reasons that make a DNS query time-consuming, and then proposed a prevention scheme using bloom filters to blacklist suspicious DNS authoritative servers. Results of our experiments show it efficiently mitigates the attack with a reasonable false positive rate.

  • 881. Zola, Enria
    et al.
    Barcelo-Arroyo, Francisco
    Dely, Peter
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Expected Bit Rate for Terminals Moving According to the Random Waypoint Model in a WLAN Cell2013Conference paper (Refereed)
    Abstract [en]

    The IEEE 802.11 standard defines the different bit rates and modulation schemes to which a WLAN device may adapt according to the channel quality. User mobility may also have an impact on the available bit rate. This paper presents a study of the bit rate evolution along time for devices that move according to the Random Waypoint mobility pattern in WLAN cells. Simulation has been applied in order to obtain statistical results that permit to characterize the evolution of the bit rate behavior along time and to compute average results in the ideal case (without interference) and in the presence of interfering devices. Our results can be useful in the solution of optimization problems in which decision on where to connect must be taken based on some minimum guaranteed bit rate. They also can be useful in the design of inter and intra-cell handover methods and load balancing schemes.

  • 882. Zola, Enrica
    et al.
    Barcelo, Francisco
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Multi-objective Optimization of WLAN Associations with Improved Handover Costs2014In: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 18, no 11Article in journal (Refereed)
    Abstract [en]

    The deployment of a large number of access points in public areas presents a new paradigm in which a given station may be served by more than one access point at a time. Recently, a network model has been proposed to derive the optimal association strategy for the stations by solving a linear optimization problem. According to that model, a station cannot download data while performing a handover. In this letter, we demonstrate that, even in static conditions (i.e., no mobility and constant load in the cell), an association strategy can force a handover. We thus propose a multi-objective optimization function that maximizes the download rates and minimizes the number of handovers. As a handover implies an extra cost due to necessary signaling to be exchanged, we propose a new handover cost function that takes into account the extra bandwidth. Using the new strategy, the system throughput slightly decreases, and the number of handovers is reduced.

  • 883. Zola, Enrica
    et al.
    Dely, Peter
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Kassler, Andreas
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science.
    Barcelo-Arroyo, Francisco
    Robust Association for Multi-radio Devices under Coverage of Multiple Networks2013Conference paper (Refereed)
  • 884. Zola, Enrica
    et al.
    Kassler, Andreas
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Energy Efficient Control of Virtual Machine Consolidation under Uncertain Input Parameters for the Cloud2015In: Proceedings of the Workshop on Engineering and Control for Reliable Cloud Services, Ghent, Belgium, September 2015, 2015Conference paper (Refereed)
  • 885.
    Zola, Enrica
    et al.
    Spain.
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Centre for HumanIT (from 2013).
    Minimizing the impact of the handover for mobile users in WLAN: A study on performance optimization2016In: Computer Networks, ISSN 1389-1286, E-ISSN 1872-7069, Vol. 107, p. 292-303Article in journal (Refereed)
    Abstract [en]

    IEEE 802.11 based Wireless LANs are an important piece in today’s communication infrastructure in order to provide high speed wireless Internet access to static or quasi mobile users. For large WLAN deployments (i.e., Campus or enterprise WLAN), it is important to understand the impact of user mobility and handovers on the system performance. In this article, we have developed a performance model for a set of networked 802.11 based WLAN Access Points, which is based on a Mixed Integer Linear Program (MILP). The objective function tries simultaneously to maximize the total system rate while at the same time minimizing the number of handovers for a configurable handover signaling rate. Because of the conflicting nature of the two objective functions, such multi-objective optimization is difficult to explore. A detailed evaluation of the model using several scenarios involving both different numbers of static and mobile users shows that our formulation allows trading off those two objectives in a robust way. 

  • 886.
    Zola, Enrica
    et al.
    Universitat Politècnica de Catalunya (UPC), Barcelona.
    Kassler, Andreas
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Optimising for Energy or Robustness? Trade-off for VM Consolidation under Uncertainty2016In: Optimization Letters, ISSN 1862-4472, E-ISSN 1862-4480Article in journal (Refereed)
    Abstract [en]

    Reducing the energy consumption of virtualized datacenters and the Cloud is very important in order to lower CO2 footprint and operational cost of a Cloud operator. However, there is a trade-off between energy consumption and perceived application performance. In order to save energy, Cloud operators want to consolidate as many Virtual Machines (VM) on the fewest possible physical servers, possibly involving overbooking of resources. However, that may involve SLA violations when many VMs run on peak load. Such consolidation is typically done using VM migration techniques, which stress the network. As a consequence, it is important to find the right balance between the energy consumption and the number of migrations to perform. Unfortunately, the resources that a VM requires are not precisely known in advance, which makes it very difficult to optimise the VM migration schedule. In this paper, we therefore propose a novel approach based on the theory of robust optimisation. We model the VM consolidation problem as a robust Mixed Integer Linear Program and allow to specify bounds for e.g. resource requirements of the VMs. We show that, by using our model, Cloud operators can effectively trade-off uncertainty of resource requirements with total energy consumption. Also, our model allows us to quantify the price of the robustness in terms of energy saving against resource requirement violations.

  • 887. Zola, Enrica
    et al.
    Kassler, Andreas
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Kim, Wooseong
    Joint User Association and Energy Aware Routing for Green Small Cell mmWave Backhaul Networks2017In: 2017 IEEE Wireless Communications and Networking Conference (WCNC), IEEE, 2017Conference paper (Refereed)
    Abstract [en]

    A dense deployment of small cells is one of the key characteristics envisioned for future 5G mobile networks in order to provide the required capacity increase. To cut cabling costs, small cells are foreseen to form multihop topologies using high capacity backhaul wireless links in the mmWave bands. Such small cells are deployed within the coverage area of a macro cell (eNB) to provide localized capacity where needed according to the well known Heterogeneous Network concept (HetNet). However, green networking will be very important because powering on unnecessarily a massive amount of small cells may lead to increased OPEX and CO2 emission. In this paper, we propose an optimization model that minimizes the total power consumption of 5G HetNets deployments while providing the required capacity and coverage. Our model jointly optimizes the user association, routing in the multihop backhaul and decides to power on or off the small cells to serve the user demands. Our numerical evaluation show significant power savings over a large range of traffic demand distributions while keeping the blocking probability low.

  • 888. Zola, Erica
    et al.
    Kassler, Andreas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Minimizing the Impact of Handover in WLAN: A Study on Performance Optimization2015In: Proceedings of SWE-CTW 2015, May 27th – 29th, Karlstad, Sweden, 2015Conference paper (Refereed)
  • 889.
    Älveborn, Andreas
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Lönnerstrand, Marcus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Kontextbaserad information genom iBeacon: En implementation i iOS och Android2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In the present day the need for relevant information at the right time and place is growing; so called context-based information. By using iBeacon based solutions this need can be largely satisfied. This dissertation explores uses for iBeacon as well as providing ideas for development. One concept which has been implemented is a mobile application for distribution of context based information in "mobility-expos". The concept has been developed for iOS and Android. The applications use a web service to facilitate distribution of information. The implementation is described in detail and important design choices are discussed and motivated.

  • 890.
    Åhlfeldt, Rose-Mharie
    et al.
    Högskolan i Skövde, Institutionen för informationsteknologi.
    Andersén, Annelie
    Högskolan i Skövde, Institutionen för hälsa och lärande.
    Eriksson, Nomie
    Högskolan i Skövde, Institutionen för handel och företagande.
    Nohlberg, Marcus
    Högskolan i Skövde, Institutionen för informationsteknologi.
    Bergström, Erik
    Högskolan i Skövde, Institutionen för informationsteknologi.
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Kompetensbehov och kompetensförsörjning inom informationssäkerhet från ett samhällsperspektiv2015Report (Other academic)
    Abstract [sv]

    På uppdrag av Myndigheten för samhällsskydd och beredskap (MSB) har en studie genomförts med syftet att komplettera resultatet från en tidigare genomförd förstudie (Åhlfeldt m.fl., 2014) med en analys av kompetensförsörjning och kompetensbehov på informations­säkerhetsområdet från ett samhällsperspektiv. Arbetet har genomförts av forskare från två lärosäten, Högskolan i Skövde och Karlstad Universitet, samt inom tre forskningsdiscipliner: pedagogik, informationssäkerhet och företagsekonomi.

    Uppdraget har varit att besvara följande frågeställningar:

    • Vilka är kompetensbehoven för att ha en god och balanserad informationssäkerhet som bidrar till samhällets informationssäkerhet?
      • Samtida kompetensbehov (nuläget)
      • Framtida kompetensbehov
      • Hur ska nödvändig kompetens erhållas och på vem ligger ansvaret?
      • Utifrån ovanstående frågeställningar, vilka är de viktigaste framgångsfaktorerna?

    Arbetet har genomförts i form av fokusgrupper med representanter från myndigheter och företag som har en nära verksamhetskoppling till samhällets informationssäkerhet och som är viktiga för att samhällets informationssäkerhet ska fungera.

    Resultatet visar att det finns stora brister avseende informationssäkerhetskompetens på alla nivåer i samhället. Tre tydliga områden pekas ut 1) nationellt - ökat behov av starkare styrning och ledning samt kravställning 2) organisation - ökat behov av kompetens från ledning till medarbetare men med starkt fokus på kompetenshöjande åtgärder på ledningsnivå samt vid upphandling och 3) medborgarperspektivet där framförallt skolområdet lyfts fram som ett viktigt insatsområde för kompetenshöjande åtgärder.

    För att uppnå nödvändig kompetens krävs utbildningsinsatser på alla ovan angivna områden. Dels utbildningar på akademisk nivå för informationssäkerhetsexperter men även övriga utbildningar inom t ex juridik och ekonomi. Även yrkesverksamma på organisationsnivå behöver riktade kompetenshöjande åtgärder som sätter informationssäkerhet i fokus utifrån organisationens verksamhetsbehov, allt ifrån ledningsnivå till medarbetarnivå.

    Resultatet visar även att ansvaret för samhällets kompetensförsörjning för informationssäkerhet ligger även den på alla ovan nämnda tre områden men med tydlig betoning på nationell nivå. Här betonas behovet av nationella krav för att medvetandegöra och lyfta informations­säkerheten i samhällsviktig verksamhet för att nå så många medborgare som möjligt.  

    Förslag på framtida arbete avseende utveckling av metoder för framtida studier av kompetensförsörjningen pekar främst på metoder för att angripa bristen på helhetssyn samt kompetensförsörjning för management och medborgare.

  • 891.
    Åhlfeldt, Rose-Mharie
    et al.
    Högskolan i Skövde, Institutionen för informationsteknologi.
    Fischer-Hübner, Simone
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Carlén, Urban
    Högskolan i Skövde, Institutionen för hälsa och lärande.
    Andersén, Annelie
    Högskolan i Skövde, Institutionen för hälsa och lärande.
    Eriksson, Nomie
    Högskolan i Skövde, Institutionen för handel och företagande.
    Björck, Fredrik
    Stockholms Universitet.
    Förstudie kompetensbehov informationssäkerhet2014Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    På uppdrag av Myndigheten för samhällsskydd och beredskap (MSB) har en förstudie genomförts med syftet att sammanställa forskningsresultat om kompetenshöjande åtgärder inom informationssäkerhetsområdet för att kartlägga utbildningsbehov och identifierade nyttoeffekter. Arbetet har genomförts av forskare från tre olika lärosäten, Högskolan Skövde, Karlstad Universitet och Stockholms Universitet, samt inom tre forskningsdiscipliner nämligen pedagogik, informationssäkerhet och företagsekonomi.

    Förstudien har haft i uppdrag att besvara följande frågeställningar:

    • Hur definieras kompetens?

    • Hur mäter man kompetens?

    • Hur skiljer sig olika typer av utbildningsinsatser avseende nyttoeffekter? Vilka erfarenheter,

      utvärderingar förklaringsfaktorer kan identifieras?

    • Hur och i vilken utsträckning tillgodogörs olika typer av utbildningar?

    • Vad kännetecknar framgångsrika utbildningsinsatser?

      Resultatet visar att kompetensbegreppet är svårdefinierat och det finns ingen tydlig definition av begreppet. Ett försök till en sammanfattande beskrivning av kompetensbegreppet utifrån granskningen är att kompetens innebär en viss uppsättning kunskaper, färdigheter, etik och attityder i en viss kontext. Kompetens innefattar både egenskaper och intentioner där egenskap inkluderar kunskap och färdighet, och intentioner innefattar etik och attityder. Allt måste dock relatera till en kontext och alltid ses i sitt sammanhang.

      Ytterst få studier har fokus på mätning av kompetens både generellt och inom informationssäkerhetsområdet. De studier som genomfört någon form av mätning mäter främst kompetens utifrån det akademiska fältet och då i första hand utifrån ett kunskapsperspektiv. Forskning av mätning på yrkesverksamma är minimal inom de sökområden som granskats i denna förstudie.

      Avseende kompetensbehov, nyttoeffekter, erfarenheter och framgångsfaktorer visar granskningen att framgångsfaktorer generellt är när utbildningsinsatserna för yrkesverksamma har ett praktiknära fokus. Motivationen och engagemanget hos de som går en utbildning är av avgörande betydelse. Det går inte direkt att avgöra vilka utbildningstyper eller aktiviteter som är av störst betydelse utan granskningen visar att en kombination av olika utbildningsformer och aktiviteter är att föredra. Vidare är dialog och diskussion i den dagliga verksamheten av stor betydelse för att bygga upp en hållbar säkerhetskultur i organisationen. Den s k tysta kunskapen ska inte underskattas utan behöver tas i beaktande och stödjas.

      Ytterligare är ledningens engagemang, delaktighet och stöd för utbildningens genomförande av avgörande betydelse om en utbildning ska uppnå en tydlig effekt i verksamheten.

      Granskningen visar att det finns behov av ytterligare forskning avseende kompetensbehov och på vilket sätt olika utbildningsinsatser ger effekt i organisationer. Förslag på ett diskussionsunderlag för framtida arbete har tagits fram. Förslagen innefattar bl a behov av kompetensanalyser, metoder och verktyg för att mäta utbildningseffekter, riktade kompetenshöjande insatser för managementnivån, longitudinella studier för uppföljning av effekter samt utveckling av metoder och verktyg för ett situerat lärande.

    Granskningen har genomförts inom olika disciplinområden vilket har uppfattats mycket positivt av de deltagande forskarna. Eftersom informationssäkerhet är ett interdisciplinärt område krävs också att bredare perspektiv och ytterligare discipliner bör ingå i framtida fördjupade analyser i området. Exempel på tillkommande discipliner är beteendevetenskap, psykologi och juridik. Behovet av kompetens inom informationssäkerhetsområdet lär inte minska i framtiden och ytterligare forskning behövs för att rätt utbildning ska nå rätt person vid rätt tidpunkt och på rätt plats.

    Skövde i mars 2014

  • 892.
    Åhs, Gustaf
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Samuelsson, Viktor
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Certifieringswebb2017Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    This report presents the work performed to develop a web application, ranging from producing a requirements specification to the implementation and a demonstration of a prototype. The availability of a web application may come with various restrictions. The restriction in this case is that access is only given to employees at Sogeti Karlstad listed on the company's server. Access to the application by other offices in Sweden is not yet implemented.

    The goal of the development of this particular web application is to simplify the management of certificates currently using Excel spreadsheets and improve accessibility of the information for Sogeti employees.An important requirement was to create a sense of competition among employees in order to increase the number of certificates taken, which results in increased value for Sogeti as well as for those employees.

    In the last two chapters of the report, the project's technical and non-technical parts are evaluated both in their entirety and in some detail of different parts of the project. This information can be useful for future students about what to take into consideration before committing to a new project. All of the essential requirements in the requirement specification were fulfilled which led to a successful project.

  • 893.
    Öhléh, Sofia
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Matematiklyftets effekter: En studie om Matematiklyftets effekter på lärares undervisning och ämnesdidaktiska kunskaper inom problemlösning2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Arbetets syfte är att undersöka vilka ämnesdidaktiska kunskaper, lärare som deltagit i Matematiklyftet, utvecklat och hur kompetensutvecklingen bidragit till deras undervisning. För att besvara frågeställningarna har lärare i årkurs 1–3, som deltagit i Matematiklyftet, intervjuats. Studien är avgränsad till undervisning i problemlösning och taluppfattning, därför har även en avgränsning i urvalet gjorts. De lärare som har intervjuats har deltagit i modulen problemlösning.  

    Matematiklyftets målsättning var bland annat att utveckla lärares ämnesdidaktiska kunskaper och på sikt öka elevernas måluppfyllelse i matematik. Studien visar att lärare som deltagit i Matematiklyftet har utvecklat ämnesdidaktiska kunskaper och nya metoder att använda i sin undervisning som berör problemlösning. I intervjuerna har lärare beskrivit hur deras undervisning och planering har påverkats av deras deltagande i Matematiklyftet. Analysarbetet av det empiriska materialet har lett fram till att specifika ämnesdidaktiska kunskaper identifierats och presenteras genom Ball, Thames och Phelps (2008) teorin för matematikundervisning (Mathematical Knowledge for Teaching).

  • 894.
    Örnefors, Maria
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science. Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Language, Literature and Intercultural Studies.
    Olika arbetssätt och arbetsformer i matematikundervisningen: En kvalitativ studie om lärares val av arbetssätt och arbetsformer i matematikundervisningen i årskurserna 1-3.2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this report is to examine which working methods and forms of work some teachers for grades 1-3, describes that they use in mathematics teaching, what makes them choose the working methods and forms of work, and if their attitude to mathematics teaching changed in recent years. In order to examine this, qualitative interviews with six teachers have been implemented. It emerged that these teachers partly use a variety of working methods and multiple forms of work in their mathematics teaching even if this differs between different teachers. Their arguments to the choice of working methods and forms of work are that they believe that the chosen working method, or form of work, works based on their own experience and partly because it is timesaving but also that changes in working methods in other topics inspired. All teachers think they have changed their attitude to mathematics teaching in different ways.

  • 895.
    Österdahl, Fredrik
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Hendo, Ilias
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Themes in Totara: Creating and cloning2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this paper is to give the reader an insight into the graphical interface of a Learning Management system, the theme, how it functions and its importance. The main point is how the creation of new themes can be done, and two different approaches are examined and compared.The use of learning management systems have been growing rapidly over the past years. Modern learning, be it basic school, higher education or professional training, is almost always supported by some learning management system where both instructors and participators share learning material, assignments, discussion, among other things.The theme of a learning management system is of great importance and can have a substantial impact on the efficiency of the actual learning process. Themes might also differ in their purpose, thus depending on the target audience, creating a specific theme might be desirable.The work done in this paper examines the structure and function of themes in the web based Totara learning management system, and looks at two different approaches to creating new themes. These approaches involve creating something from scratch, and cloning an already existing theme.The conclusion drawn from the work done in this paper is that the most efficient way of creating a new theme, is through cloning an already existing theme. Only when time and experience is plentiful, and a full control over the theme structure is desirable, is creating a theme from scratch a viable option.

  • 896.
    Österholm, Magnus
    et al.
    Umeå universitet, Umeå forskningscentrum för matematikdidaktik (UFM).
    Bergqvist, Tomas
    Umeå universitet, Institutionen för tillämpad utbildningsvetenskap.
    Liljekvist, Yvonne
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Uppsala universitet.
    van Bommel, Jorryt
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Utvärdering av Matematiklyftets resultat: slutrapport2016Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    Matematiklyftet är en fortbildning för alla lärare i Sverige som undervisar i matematik. Den genomfördes 2012-2016. Kärnan i fortbildningen var det kollegiala lärandet. Lärare arbetade tillsammans med olika moduler som var och en bestod av didaktiskt material att använda vid planering, diskuss-ioner och genomförande av matematikundervisning, samt vid kollegiala reflektioner och diskussioner. Genom modulerna belystes primärt fyra olika didaktiska perspektiv: (1) att undervisa matematik utifrån förmågorna, (2) bedömning för lärande och undervisning i matematik, dvs. formativ bedömning, (3) rutiner/interaktioner i klassrummet och (4) klassrumsnormer/sociomatematiska normer.

    Denna rapport presenterar en utvärdering av Matematiklyftets resultat där det undersökts i vilken utsträckning Matematiklyftet har bidragit till att utveckla en bestående undervisningskultur och en bestående fortbildningskultur. Utvärderingen syftar också till att identifiera faktorer som gynnar eller missgynnar Matematiklyftets resultat och ska även fungera både formativt och summativt. Det innebär att både slutsatser om hur Matematiklyftet har uppnått målen att utveckla undervisnings- och fortbildningskulturen och slutsatser om hur stöd till planeringar och genomförande av liknande fort-bildningssatsningar formuleras. Urvalet i utvärderingen består av 35 grund-och gymnasieskolor. På varje skola har tre lärare slumpmässigt valts ut att ingå i utvärderingen, dvs. totalt 105 lärare. I utvärderingen ingår också varje skolas rektor och representant för skolhuvudman. Skolorna har besökts vid två tillfällen för att kunna undersöka förändring i undervisnings- och fortbildningskultur. Datamaterialet består av observationer av matematiklektioner och av kollegiala samtal, intervjuer och enkäter med lärare och rektorer, samt intervjuer med representanter för skolhuvudmän. I datamaterialet ingår även insamlade dokument (t.ex. fortbildningsplaner och kopior av undervisningsmaterial) och bakgrundsinformation om de besökta skolorna (från externa databaser). Denna rapport utgör slutrapporten för utvärderingen av Matematiklyftets resultat. Nedan redovisas utvärderingens huvudsakliga resultat tillsammans med rekommendationer inför framtida fortbildningssatsningar av samma typ som Matematiklyftet.

  • 897.
    Österholm, Magnus
    et al.
    Umeå universitet.
    Bergqvist, Tomas
    Umeå universitet.
    van Bommel, Jorryt
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Liljekvist, Yvonne
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Utvärdering av matematiklyftets resultat: delrapport 12014Report (Other academic)
    Abstract [sv]

    Denna rapport är en första delrapport inom utvärderingen av Matematiklyftets resultat. I detta skede har utvärderingen pågått i cirka sex månader. Arbetet har under denna period till största delen bestått av planeringsarbete inför kommande insamling och analyser av data. 

  • 898.
    Österling Sicking, Sigrid
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Hegna Tengstål, Vidar
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Tjänstebaserad Business Intelligence med Power BI i en webbapplikation2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Business Intelligence is about helping companies making business beneficial decisions by analysing and visualising data with the help of tools and applications. QBIM is a company in Karlstad that provides their customers with service based BI in various branches. They use a software called Power BI to compile the data from their customers and display the results in their portal SKI-ANALYTICS. The portal has as of now many flaws, and this report will focus on identify and improve those flaws. This goal will be split up and done in three parts; Q&A embedding, report embedding and mobile adaptation. The improvements will be implemented with the use of Power BI REST API and Power BI JavaScript API. The result is a more user friendly and attractive customer portal, where the three part goals are implemented. The report also includes a discussion on pros and cons of the use of an API that severely limits the freedom of the developer.

  • 899.
    Özgü, Alay
    et al.
    Simula Metropolitan Center for Digital Engineering, Norge.
    Mancuso, Vincenzo
    IMDEA Networks Institute, Spanien.
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Alfredsson, Stefan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Mellia, Marco
    Politecnico di Torino, Italien.
    Bernini, Giacomo
    Nextworks, Italien.
    Lonsethagen, Hakon
    Telenor Research, Norge.
    End to End 5G Measurements with MONROE: Challenges and Opportunities2018In: 4th International Forum on Research and Technologies for Society and Industry (IEEE RTSI 2018), IEEE, 2018Conference paper (Refereed)
    Abstract [en]

    To be able to support diverse requirements of massive number of connected devices while also ensuring good user experience, 5G networks will leverage multi-access technolo- gies, deploy supporting operational mechanisms such as SDN and NFV, and require enhanced protocols and algorithms. For 4G networks, MONROE has been key to provide a common measurement platform and a set of methodologies available to the wider community. Such common grounds will become even more important and more challenging with 5G. In this paper, we elaborate on some key requirements for the design and implementation of 5G technologies and highlight the key challenges and needs for new solutions as seen in the context of 5G end-to-end measurements. We then discuss the opportunities that MONROE provides and more specifically, how a 5G-capable MONROE platform could facilitate these efforts.

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