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  • 301.
    Gogatishvili, Amiran
    et al.
    Czech Acad Sci, Inst Math, Prague, Czech Republic.
    Křepela, Martin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Univ Freiburg, Inst Math.
    Pick, Lubos
    Charles Univ Prague, Czech republic.
    Soudsky, Filip
    Czech Tech Univ; Univ South Bohemia, Czech republic.
    Embeddings of Lorentz-type spaces involving weighted integral means2017In: Journal of Functional Analysis, ISSN 0022-1236, E-ISSN 1096-0783, Vol. 273, no 9, p. 2939-2980Article in journal (Refereed)
    Abstract [en]

    We solve the problem of characterizing weights on (0, infinity) for which the inequality involving two possibly different general inner weighted means (integral(infinity)(0)(integral(t)(0)f*(s)(m2)u(2)(s)ds)(p2/m2) w(2)(t)dt)(1/p2) <= C(integral(infinity)(0)(integral(t)(0)f*(s)(m2)u(1)(s)ds)(p1/m1) w(1)(t)dt)(1/p1) holds, where p(1), p(2), m(1), m(2) is an element of (0, infinity) and p(2) > m(2). The proof is based on a new approach combining duality techniques with sharp weighted estimates for iterated integral and supremum operators. (C) 2017 Elsevier Inc. All rights reserved.

  • 302.
    Gokan Khan, Michel
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Bastani, Saeed
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Taheri, Javid
    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).
    Deng, Shuigang
    Zhejiang Univ, China.
    NFV-Inspector: A Systematic Approach to Profile and Analyze Virtual Network Functions2018In: 2018 IEEE 7th International Conference on Cloud Networking (CloudNet), IEEE, 2018, p. 1-7Conference paper (Refereed)
    Abstract [en]

    Network Function Virtualization (NFV) focuses on decoupling network functions from proprietary hardware (i.e., middleboxes) by leveraging virtualization technology. Combining it with Software Defined Networking (SDN) enables us to chain network services much easier and faster. The main idea of using these technologies is to consolidate several Virtual Network Functions (VNFs) into a fewer number of commodity servers to reduce costs, increase VNFs fluidity and improve resource efficiency. However, the resource allocation and placement of VNFs in the network is a multifaceted decision problem that depends on many factors, including VNFs resource demand characteristics, arrival rate, configuration of underlying infrastructure, available resources and agreed Quality of Services (QoS) in Service Level Agreements (SLAs). This paper presents a bottom-up open-source NFV analysis platform (NFV-Inspector) to (1) systematically profile and classify VNFs based on resource capacities, traffic demand rate, underlying system properties, placement of VNFs in the network, etc. and (2) extract/calculate the correlation among the QoS metrics and resource utilization of VNFs. We evaluated our approach using an emulated virtual Evolved Packet Core platform (Open5GCore) to showcase how complex relation among various NFV service chains can be systematically profiled and analyzed.

  • 303.
    Gokan Khan, Michel
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Taheri, Javid
    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).
    Darula, Marian
    R&D Technology and Industry, Ericsson, Sweden.
    Automated Analysis and Profiling of VirtualNetwork Functions: the NFV-Inspector Approach2018In: 2018 IEEE Conference on Network Function Virtualization and Software Defined Networks (NFV-SDN), IEEE, 2018Conference paper (Refereed)
    Abstract [en]

    Discovering insights about Virtual Network Function (VNFs) resource demand characteristics will enable cloud vendors to optimize their underlying Network Function Virtualization (NFV) system orchestration and dramatically mitigate CapEx and OpEx spendings. However, analyzing large-scale NFV systems, especially in mobile network environments, is a challenging task and requires tailor-made approaches for each particular application. In this demo, we showcase NFV-Inspector, an open source and extensible VNF analysis platform that is capable of systematically benchmark and profile NFV deployments. Based on its pluggable framework, NFV-Inspector classifies VNFs resource demand characteristics and correlate their Key Performance Indicators (KPIs) with system-level Quality of Service (QoS) measurements. 

  • 304.
    Granath, Håkan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    The discriminant 10 Shimura curve and its associated Heun functions2016In: Bulletin of the London Mathematical Society, ISSN 0024-6093, E-ISSN 1469-2120, Vol. 48, p. 957-967Article in journal (Refereed)
    Abstract [en]

    The Shimura curve of discriminant 10 is uniformized by a subgroup of an arithmetic $(2,2,2,3)$ quadrilateral group. We derive the differential structure of the ring of modular forms for the Shimura curve and relate the ring generators to explicit Heun functions for the quadrilateral group. We also show that the Picard–Fuchs equation of the associated family of abelian surfaces has solutions that are modular forms. These results are used to completely describe the exceptional sets of the Heun functions, and we show how to find examples like \[ Hl\left(\frac{27}{2},\frac{7}{36}; \frac{1}{12},\frac{7}{12},\frac{2}{3},\frac{1}{2}; -\frac{96}{25}\right)=\frac{2^{1/2}5^{2/3}}{3^{4/3}}. \]

  • 305.
    Granath, Håkan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Baba, Srinath
    Concordia University, Canada.
    Differential equations and expansions for quaternionic modular forms in the discriminant 6 case2012In: LMS Journal of Computation and Mathematics, ISSN 1461-1570, E-ISSN 1461-1570, Vol. 15, p. 385-399Article in journal (Refereed)
    Abstract [en]

    We study the differential structure of the ring of modular forms for the unit group of the quaternion algebra over Q of discriminant 6. Using these results we give an explicit formula for Taylor expansions of the modular forms at the elliptic points. Using appropriate normalizations we show that the Taylor coefficients at the elliptic points of the generators of the ring of modular forms are all rational and 6-integral. This gives a rational structure on the ring of modular forms. We give a recursive formula for computing the Taylor coefficients of modular forms at elliptic points and, as an application, give an algorithm for computing modular polynomials.

  • 306.
    Granström, Frida
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Symmetry methods and some nonlinear differential equations: Background and illustrative examples2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Differential equations, in particular the nonlinear ones, are commonly used in formulating most of the fundamental laws of nature as well as many technological problems, among others. This makes the need for methods in finding closed form solutions to such equations all-important. In this thesis we study Lie symmetry methods for some nonlinear ordinary differential equations (ODE). The study focuses on identifying and using the underlying symmetries of the given first order nonlinear ordinary differential equation. An extension of the method to higher order ODE is also discussed. Several illustrative examples are presented.

  • 307.
    Grazia, Carlo Augusto
    et al.
    University of Modena and Reggio Emilia, Italy.
    Patriciello, Natale
    Centre Tecnológic de Telecomunicacions de Catalunya, Spain.
    Høiland-Jørgensen, Toke
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Klapez, Martin
    University of Modena and Reggio Emilia, Italy.
    Casoni, Maurizio
    University of Modena and Reggio Emilia, Italy.
    Mangues-Bafalluy, Josep
    Centre Tecnológic de Telecomunicacions de Catalunya, Spain.
    Adapting TCP Small Queues for IEEE 802.11 Networks2018In: 2018 IEEE 29Th Annual International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC), IEEE, 2018Conference paper (Refereed)
    Abstract [en]

    In recent years, the Linux kernel has adopted an algorithm calledTCP Small Queues (TSQ) for reducing queueing latency by controlling buffering in the networking stack.This solution consists of a back-pressure mechanism that limitsthe number of TCP segments within the sender TCP/IP stack, waitingfor packets to actually be transmitted onto the wire beforeenqueueing further segments.Unfortunately, TSQ prevents the frameaggregation mechanism in the IEEE 802.11n/ac standards from achieving itsmaximum aggregation, because not enough packets are available in the queue to buildaggregates from, which severely limits achievable throughput over wirelesslinks.This paper demonstrates this limitation of TSQ in wireless networks and proposesControlled TSQ (CoTSQ), a solution that improves TSQ so that it controls the amountof data buffered while allowing the IEEE 802.11n/ac aggregation logic to fullyexploit the available channel and achieve high throughput. Results on a real testbed show that CoTSQ leadsto a doubling of throughput on 802.11n and up to an order of magnitudeimprovement in 802.11ac networks, with a negligible latency increase.

  • 308.
    Gregebo, Victor
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Nilsson, Jonas
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Struktur på den digitala arbetsplatsen2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The concept the digital workplace can be viewed as a collection of all tools and IT systems that are used while working digitally. The digital workplace needs an internal communication strategy that describes how information is being managed in order to get a better information structure in the digital tools. This structure is needed to make more efficient use of the tools. Fabriken believes the intranet is the tool that can connect all tools in the digital workplace.

    The strategies describe where employees can either find or share information within the organization. If a communication strategy has not been developed, disadvantages such as redundancy, duplicated information and difficulties in finding the correct information may occur.

    The goal of this study is to develop an internal communication strategy and explore whether the intranet could become a central part in Fabriken's digital workplace. The communication strategy has been developed by collecting data from interviews and workshops. To make the communication strategy a reality, a Proof of Concept (PoC) was planned to be developed. The objective of this PoC is to show possibilities of the strategy where Fabriken can decide if they want to further develop it. Due to lack of time a PoC was never developed.

    This study has resulted in a communication strategy and suggested changes to the intranet. These changes involve intranets availability and a solution consisting of a knowledge bank.

  • 309.
    Greschbach, Benjamin
    et al.
    KTH Royal Institute of Tech. .
    Pulls, Tobias
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Roberts, Laura M.
    Princeton University.
    Winter, Philipp
    Princeton University.
    Feamster, Nick
    Princeton University.
    The Effect of DNS on Tor´s Anonymity2017In: NDSS Symposium 2017, Internet society , 2017Conference paper (Refereed)
    Abstract [en]

    Previous attacks that link the sender and receiver oftraffic in the Tor network (“correlation attacks”) have generallyrelied on analyzing traffic from TCP connections. The TCPconnections of a typical client application, however, are oftenaccompanied by DNS requests and responses. This additionaltraffic presents more opportunities for correlation attacks. Thispaper quantifies how DNS traffic can make Tor users more vulnerableto correlation attacks. We investigate how incorporatingDNS traffic can make existing correlation attacks more powerfuland how DNS lookups can leak information to third partiesabout anonymous communication. We (i) develop a method toidentify the DNS resolvers of Tor exit relays; (ii) develop a newset of correlation attacks (DefecTor attacks) that incorporate DNStraffic to improve precision; (iii) analyze the Internet-scale effectsof these new attacks on Tor users; and (iv) develop improvedmethods to evaluate correlation attacks. First, we find that thereexist adversaries that can mount DefecTor attacks: for example,Google’s DNS resolver observes almost 40% of all DNS requestsexiting the Tor network. We also find that DNS requests oftentraverse ASes that the corresponding TCP connections do nottransit, enabling additional ASes to gain information about Torusers’ traffic. We then show that an adversary that can mount aDefecTor attack can often determine the website that a Tor useris visiting with perfect precision, particularly for less popularwebsites where the set of DNS names associated with that websitemay be unique to the site. We also use the Tor Path Simulator(TorPS) in combination with traceroute data from vantage pointsco-located with Tor exit relays to estimate the power of AS-leveladversaries that might mount DefecTor attacks in practice.

  • 310.
    Grinnemo, Karl-Johan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Bozakov, Zdravko
    Dell EMC.
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Isabel Bueno, María
    Damjanovic, Dragana
    Mozilla.
    Rikter Evensen, Kristian
    Celerway.
    Fairhurst, Gorry
    University of Aberdeen, UK..
    Hansen, Audun
    Celerway.
    Hayes, David
    University of Oslo, Norway.
    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, Norway.
    Mangiante, Simone
    Dell EMC.
    Mohideen, Althaff
    University of Aberdeen, UK..
    Rajiullah, Mohammad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Ros, David
    Simula.
    Rüngeler, Irene
    FH Münster, Germany.
    Santos, Ricardo
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Secchi, Raffaello
    University of Aberdeen, UK..
    Christian Tangenes, Tor
    Tüxen, Micheal
    FH Münster, Germany.
    Weinrank, Felix
    FH Münster, Germany.
    Welzl, Michael
    University of Oslo, Norway.
    Deliverable D3.1 - Initial Report on the Extended Transport System2017Report (Refereed)
    Abstract [en]

    The NEAT System offers an enhanced API for applications that disentangles them from the actual transport protocol being used. The system also enables applications to communicate their service requirements to the transport system in a generic, transport-protocol independent way. Moreover, the architecture of the NEAT System promotes the evolution of new transport services. Work Package 3 (WP3) enhances and extends the core parts of the NEAT Transport. Efforts have been devoted to developing transport-protocol mechanisms that enable a wider spectrum of NEAT Transport Services, and that assist the NEAT System in facilitating several of the commercial use cases. Work has also started on the development of optimal transport-selection mechanisms; mechanisms that enable for the NEAT System to make optimal transport selections on the basis of application requirements and network measurements. Lastly, another research activity has been initiated on how to use SDN to signal application requirements to routers, switches, and similar network elements. This document provides an initial report on all these WP3 activities—both on completed and on near-termplanned work.

  • 311.
    Grinnemo, Karl-Johan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Bozakov, Zdravko
    Dell EMC.
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Isabel Sanchez Bueno, Maria
    Dreibholz, Thomas
    Simula.
    Rikter Evensen, Kristian
    Celerway.
    Fairhurst, Gorry
    University of Aberdeen, UK..
    Fosselie Hansen, Audun
    Celerway.
    Hayes, David
    University of Oslo, Norway.
    Hurtig, Per
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Rajiullah, Mohammad
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Jones, Tom
    University of Aberdeen, UK..
    Ros, David
    Simula.
    Rozensztrauch, Tomasz
    Celerway.
    Tüxen, Michael
    FH Münster, Germany.
    Vyncke, Eric
    CISCO.
    Deliverable D3.3 - Extended Transport System and Transparent Support of Non-NEAT Applications2017Report (Refereed)
    Abstract [en]

    This deliverable summarises and concludes our work in Work Package 3 (WP3) to extend the transport services provided by the NEAT System developed in Work Package 2, and to enable non-NEAT applications to harness the transport services offered by NEAT. We have demonstrated how a policy- and information-based selection of transport protocol by NEAT could provide a more efficient transport service for web applications. The information on which NEAT makes its transport selection decisions resides in the Characteristics Information Base (CIB). The CIB is populated by various CIB sources, and in WP3 we have designed, implemented, and evaluated various CIB sources, including meta data from mobile broadband networks, passive measurements, IPv6 Provisioning Domain protocols and the Happy Eyeballs mechanism, which caches the outcome of its connection attempts. A key property of NEAT is that it not only “vertically” decouples applications from transport protocols, but also “horizontally”. Particularly, it enables applications to harness information about resource availability and policies from Software Defined Networking (SDN) controllers in managed networks, without these applications actually being SDN-aware. To extend the use of NEAT to non-NEAT applications, we have implemented a BSDcompatible sockets API on top of NEAT and a NEAT proxy that intercepts and replaces standard TCP connections with NEAT flows, i.e., with the transport solutions deemed most appropriate by NEAT.We have also proposed a way for non-NEAT applications to make use of NEAT through the deployment of NEAT-enabled virtual appliances in SDN-controlled networks: connections from these applications are routed via an SDN-controlled proxy that terminates the original connection and replaces it with a NEAT-selected connection.

  • 312.
    Grinnemo, Karl-Johan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Brunstrom, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Cheng, Jun
    Ericsson AB, Stockholm, Sweden.
    Using Concurrent Multipath Transfer to Improve the SCTP Startup Behavior for PSTN Signaling Traffic2014In: 2014 28TH INTERNATIONAL CONFERENCE ON ADVANCED INFORMATION NETWORKING AND APPLICATIONS WORKSHOPS (WAINA) / [ed] Barolli, L; Li, KF; Enokido, T; Xhafa, F; Takizawa, M, IEEE, 2014, p. 772-778Conference paper (Refereed)
    Abstract [en]

    Although latency in the Internet has gained much attention in the research community, the latency issues of mobile control signaling have received less attention, and this all the while many telecom operators are experiencing a several-hundred percent increase in signaling traffic over only a couple of years. We believe one way to address both the latency and increased signaling load of mobile networks, is to exploit concurrent transfer of signaling traffic over several paths a.k.a. concurrent multipath transfer. This paper studies whether or not SCTP extended with concurrent multipath transfer (CMT-SCTP) could provide a faster startup behavior than standard SCTP. The paper complements previous work on CMT-SCTP, and extends it to PSTN signaling traffic. The paper suggests that CMT-SCTP could give a faster startup behavior over paths with similar bandwidths and round-trip times, but that its behavior is sensitive to differences in round-trip time between the paths. Moreover, the paper suggests that provided CMT-SCTP is configured with large enough send and receive buffers, it could provide a faster startup behavior than standard SCTP over a multipath association, in spite of some of the paths having a packet-loss rate of several percent.

  • 313.
    Grinnemo, Karl-Johan
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Brunström, Anna
    Karlstad University, Faculty of Economic Sciences, Communication and IT, Department of Computer Science. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    A First Study on Using MPTCP to Reduce Latency for Cloud Based Mobile Applications2015In: 2015 IEEE SYMPOSIUM ON COMPUTERS AND COMMUNICATION (ISCC), IEEE, 2015, p. 64-69Conference paper (Refereed)
    Abstract [en]

    Currently, Multipath TCP (MPTCP) – a modifica- tion to standard TCP that enables the concurrent use of several network paths in a single TCP connection – is being standardized by IETF. This paper provides a comprehensive evaluation of the use of MPTCP to reduce latency and thus improve the quality of experience or QoE for cloud-based applications. In particular, the paper considers the possible reductions in latency that could be obtained by using MPTCP and multiple network paths between a cloud service and a mobile end user. To obtain an appreciation of the expected latency performance for different types of cloud traffic, three applications are studied, Netflix, Google Maps, and Google Docs, representing typical applications generating high-, mid-, and low-intensity traffic. The results suggest that MPTCP could provide significant latency reductions for cloud applications, especially for applications such as Netflix and Google Maps. Moreover, the results suggest that MPTCP offers a reduced latency despite a few percent packet loss, and in spite of limited differences in the round-trip times of the network paths in an MPTCP connection. Still, larger differences in the round-trip times seem to significantly increase the application latency, especially for Netflix, Google Maps, and similar applications. Thus, to become an even better alternative to these applications, this paper suggests that the MPTCP packet scheduling policy should be changed: Apart from the round-trip times of the network paths in a connection, it should also consider the difference in round-trip time between the network paths.

  • 314.
    Grinnemo, Karl-Johan
    et al.
    Karlstad University, Faculty of Economic Sciences, Communication and IT.
    Brunström, Anna
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    A Survey of TCP-Friendly Congestion Control Mechanisms for Multimedia Traffic2003Report (Other academic)
    Abstract [en]

    The stability and performance of the Internet to date have in a large part been due tothe congestion control mechanism employed by TCP. However, while the TCP congestioncontrol is appropriate for traditional applications such as bulk data transfer, it hasbeen found less than ideal for multimedia applications. In particular, audio and videostreaming applications have difficulties managing the rate halving performed by TCP inresponse to congestion. To this end, the majority of multimedia applications use eithera congestion control scheme which reacts less drastic to congestion and therefore oftenis more aggressive than TCP, or, worse yet, no congestion control whatsoever. Sincethe Internet community strongly fears that a rapid deployment of multimedia applicationswhich do not behave in a fair and TCP-friendly manner could endanger the currentstability and performance of the Internet, a broad spectrum of TCP-friendly congestioncontrol schemes have been proposed. In this report, a survey over contemporary proposalsof TCP-friendly congestion control mechanisms for multimedia traffic in the Internetis presented. A classification scheme is outlined which shows how the majority of theproposed congestion control schemes emanate from a relatively small number of designprinciples. Furthermore, we illustrate how these design principles have been applied ina selection of congestion control scheme proposals and actual transport protocols.

  • 315.
    Grinnemo, Karl-Johan
    et al.
    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).
    Fairhurst, Gorry
    University of Aberdeen, UK..
    Hayes, David
    University of Oslo, Norway.
    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, Norway.
    Ros, David
    Simula.
    Rüngeler, Irene
    FH Münster, Germany.
    Tüxen, Michael
    FH Münster, Germany.
    Weinrank, Felix
    FH Münster, Germany.
    Welzl, Michael
    University of Oslo, Norway.
    Deliverable D3.2 - Final Report on Transport Protocol Enhancements2017Report (Refereed)
    Abstract [en]

    This deliverable provides a final report on the work on transport protocol enhancements done inWork Package 3. First, we report on the extensions made to the SCTP protocol that turn it into a viable alternative to TCP and allow to deliver a lower-latency transport service. Next, we describe our work to develop a framework for providing a deadline-aware, less-than-best-effort transport service, targeting background traffic and thus addressing requirements on NEAT from the EMC use case. We also present our efforts to design and implement a latency-aware scheduler for MPTCP, which enables NEAT to offer a transport service that meets the needs of latency-sensitive applications, and that efficiently utilises available network resources. Lastly, this document informs on our work on coupled congestion control for TCP, a mechanism that treats a bundle of parallel TCP flows between the same pair of hosts as a single unit. By efficiently multiplexing concurrent TCP flows, our coupled congestion control alleviates the effects of queueing, and tends to result in a more efficient usage of available bandwidth, where the flows’ aggregate capacity share can be apportioned based on application preferences.

  • 316.
    Grinnemo, Karl-Johan
    et al.
    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. Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Jones, Tom
    University of Aberdeen.
    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).
    Ros, David
    Simula Research Lab.
    NEAT - A New, Evolutive API and Transport-Layer Architecture for the Internet2016In: 12th Swedish National Computer Networking Workshop (SNCNW 2016), Sundsvall, Sweden., 2016Conference paper (Other academic)
    Abstract [en]

    There is a growing concern that the Internet trans- port layer has become ossified in the face of emerging novel applications, and that further evolution has become very difficult. This paper identifies requirements for a new transport layer and then proposes a conceptual architecture, the NEAT system, that we believe is both flexible and evolvable. Applications interface the NEAT system through an enhanced user API that decouples them from the operation of the transport protocols and the network features being used. In particular, applications provide the NEAT system with information about their traffic requirements, pre- specified policies, and measured network conditions. On the basis of this information, the NEAT system establishes and configures appropriate connections. 

  • 317.
    Grinnemo, Karl-Johan
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Jones, Tom
    University of Aberdeen, Aberdeen, U.K.
    Fairhurst, Gorry
    University of Aberdeen, Aberdeen, U.K.
    Ros, David
    Simula Research Laboratory, Oslo, Norway.
    Brunström, Anna
    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).
    Towards a Flexible Internet Transport Layer Architecture2016In: The 22nd IEEE International Symposium on Local and Metropolitan Area Networks (LANMAN), Rome, Italy, June 2015 / [ed] IEEE, IEEE, 2016Conference paper (Refereed)
    Abstract [en]

    There is a growing concern that the Internet trans- port layer has stagnated and become less adaptive to the requirements imposed by new applications, and that further evolution has become very difficult. This is because a fundamental assumption no longer holds: it can no longer be assumed that the transport layer is only in the scope of end-hosts. The success of TCP and UDP and the ubiquity of middleboxes have led to ossification of both the network infrastructure and the API presented to applications. This has led to the development of workarounds, and a range of point solutions that fail to cover many facets of the problem. To address this issue, this paper identifies requirements for a new transport layer and then proposes a conceptual architecture that we argue is both flexible and evolvable. This new architecture requires that applications interface to the transport at a higher abstraction level, where an application can express communication preferences via a new richer API. Protocol machinery can use this information to decide which of the available transport protocols is used. By placing the protocol machinery in the transport layer, the new architecture can allow for new protocols to be deployed and enable evolution of the transport layer. 

  • 318.
    Gruetzner, Simon
    et al.
    University of Bremen, Germany.
    Muntean, Adrian
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Brief Introduction to Damage Mechanics and its Relation to Deformations2018In: Mathematical Analysis of Continuum Mechanics and Industrial Applications II / [ed] P. VanMeurs, M Kimura, H Notsu, Springer, 2018, Vol. 30, p. 115-124Conference paper (Refereed)
    Abstract [en]

    We discuss some principle concepts of damage mechanics and outline a possibility to address the open question of the damage-to-deformation relation by suggesting a parameter identification setting. To this end, we introduce a variable motivated by the physical damage phenomenon and comment on its accessibility through measurements. We give an extensive survey on analytic results and present an isotropic irreversible partial damage model in a dynamic mechanical setting in form of a second order hyperbolic equation coupled with an ordinary differential equation for the damage evolution. We end with a note on a possible parameter identification setting.

  • 319.
    Gupta, Lay
    et al.
    Washington Univ, Dept Comp Sci & Engn, St Louis, MO 63110 USA..
    Jain, Raj
    Washington Univ, Dept Comp Sci & Engn, St Louis, MO 63110 USA..
    Erbad, Aiman
    Qatar Univ, Dept Comp Sci & Engn, Doha, Qatar..
    Bhamare, Deval
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    The P-ART framework for placement of virtual network services in a multi-cloud environment2019In: Computer Communications, ISSN 0140-3664, E-ISSN 1873-703X, Vol. 139, p. 103-122Article in journal (Refereed)
    Abstract [en]

    Carriers' network services are distributed, dynamic, and investment intensive. Deploying them as virtual network services (VNS) brings the promise of low-cost agile deployments, which reduce time to market new services. If these virtual services are hosted dynamically over multiple clouds, greater flexibility in optimizing performance and cost can be achieved. On the flip side, when orchestrated over multiple clouds, the stringent performance norms for carrier services become difficult to meet, necessitating novel and innovative placement strategies. In selecting the appropriate combination of clouds for placement, it is important to look ahead and visualize the environment that will exist at the time a virtual network service is actually activated. This serves multiple purposes - clouds can be selected to optimize the cost, the chosen performance parameters can be kept within the defined limits, and the speed of placement can be increased. In this paper, we propose the P-ART (Predictive-Adaptive Real Time) framework that relies on predictive-deductive features to achieve these objectives. With so much riding on predictions, we include in our framework a novel concept-drift compensation technique to make the predictions closer to reality by taking care of long-term traffic variations. At the same time, near real-time update of the prediction models takes care of sudden short-term variations. These predictions are then used by a new randomized placement heuristic that carries out a fast cloud selection using a least-cost latency-constrained policy. An empirical analysis carried out using datasets from a queuing-theoretic model and also through implementation on CloudLab, proves the effectiveness of the PART framework. The placement system works fast, placing thousands of functions in a sub-minute time frame with a high acceptance ratio, making it suitable for dynamic placement. We expect the framework to be an important step in making the deployment of carrier-grade VNS on multi-cloud systems, using network function virtualization (NFV), a reality.

  • 320.
    Gutmann, Andreas
    et al.
    Tech Univ Darmstadt, Darmstadt, Germany.
    Renaud, Karen
    Glasgow University, Scotland.
    Maguire, Joseph
    Glasgow University, Scotland.
    Mayer, Peter
    Tech Univ Darmstadt, Darmstadt, Germany.
    Volkamer, Melanie
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science. Tech Univ Darmstadt, Darmstadt, Germany.
    Matsuura, Kanta
    University Tokyo, Japan.
    Müller-Quade, Jörn
    Karlsruhe Inst Technol, Germany.
    ZeTA - Zero-Trust Authentication: Relying on Innate Human Ability, not Technology2016In: 2016 IEEE European Symposium on Security and Privacy (EuroS&P), IEEE, 2016, p. 357-371Conference paper (Refereed)
    Abstract [en]

    Reliable authentication requires the devices and channels involved in theprocess to be trustworthy; otherwise authentication secrets can easily becompromised. Given the unceasing efforts of attackers worldwide suchtrustworthiness is increasingly not a given. A variety of technicalsolutions, such as utilising multiple devices/channels and verificationprotocols, has the potential to mitigate the threat of untrustedcommunications to a certain extent. Yet such technical solutions make twoassumptions: (1) users have access to multiple devices and (2) attackerswill not resort to hacking the human, using social engineering techniques.In this paper, we propose and explore the potential of using human-basedcomputation instead of solely technical solutions to mitigate the threat ofuntrusted devices and channels. ZeTA (Zero  Trust Authentication on untrusted channels) has the potentialto allow people to authenticate despite compromised channels orcommunications and easily observed usage. Our contributions are threefold:(1) We propose the ZeTA protocol with a formal definition and securityanalysis that utilises semantics and human-based computation to amelioratethe problem of untrusted devices and channels.(2) We  outline a security analysis to assess the envisaged performance ofthe proposed authentication protocol.(3) We report on  a  usability study that explores the viability of relyingon human computation in this context.

  • 321. Gutmann, Andreas
    et al.
    Renaud, Karen
    Volkamer, Melanie
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Nudging Bank Account Holders Towards More Secure PIN Management2015In: Journal of Internet Technology and Secured Transactions, ISSN 1748-569X, Vol. 4, p. 380-386Article in journal (Refereed)
    Abstract [en]

    The memorability of PINs is an enduring security issue. This is especially pertinent in the context of banking, where technical systems evolve more slowly than in other contexts (e.g. many mobile phone operating systems have adopted alternative authentication mechanisms). Banking customers who struggle to memorise all their PINs often record them, sometimes insecurely, flying in the face of advice from their banks. Banks respond to memorisation difficulties by permitting customers to change their PINs. The reality is that both recording and changing unwittingly weakens the mechanism by increasing predictability. Yet trying to forbid these coping strategies is futile. It is far better to acknowledge the prevalence of such behaviours and to try to nudge people towards more secure PIN management. In this paper, we suggest a way of achieving this.

  • 322.
    Guzhva, Oksana
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Lärares kompetensutveckling och digitalisering av matematikundervisning: En enkätstudie om hur lågstadielärare kompetensutvecklar sig för att bemöta digitalisering av matematikundervisning2018Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to research how primary school teachers developed their professional competences/knowledges to meet the demands placed on them regarding the digitalization of mathematics education and how this is related to their perceived knowledges and their use of ICT in mathematics education. In order to fulfill the purpose, the empirical data of the study was collected through a questionnaire, which answered by 76 primary school teachers.

    The result showed that the majority of teachers developed their professional competences/knowledges in a variety of ways, both I the formal and informal arena. Moreover, the result indicated that the prime school teachers who engaged in online professional development activities in the formal arena combined with both online and traditional development activities in the informal area, highly experienced their knowledges in the TCK, TPK och TPACK sub-areas and used ICT in the most variety ways in the most mathematical areas. Furthermore, it also emerged the majority of primary school teachers engaged in both online and traditional development activities in both areas. These primary school teachers experienced good knowledge in all three sub-areas, but their ICT usage was on the average level for all the professional development model of the study. 

  • 323.
    Haglund, Kristoffer
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Qiu, Jia
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Documentation and implementation of interfaces for an embedded platform2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Using a new platform can be challenging, especially with relatively newly released platform and developer equipment. Difficulties and problems can arise during development from both hardware and software, some problems can be solved but sometimes help must be requested from the developers of the products.

    The consulting firm Altran in Karlstad has been dealing with this and has developed embedded software used in industrial welders for cars. There have been some uncertainty during their work, which has given birth to this project. The purpose of this project was to reconstruct and document Altran's initial development process, to make the process faster and easier for new developers. Besides the reconstruction, a discovery of unused features and components also became an important part of this project.

    The project has resulted in a documentation of various interfaces, an clock in system application called "Personnel Interactive Display and Educator", and a safe update application for the system.

  • 324.
    Haile, Habtegebreil Kassaye
    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).
    Grinnemo, Karl-Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Rate Measurement Over Short Time Scales inStationary Cellular Receivers2019In: Proceedings of the 3rd Workshop on Mobile Network Measurement (MNM 2019), Paris, France, June 2019, 2019Conference paper (Refereed)
    Abstract [en]

    An increasing number of cellular congestion controlalgorithms (CCAs) are relying on measurements of the deliveryrate observed at the receiver. Accordingly, early detection ofchanges in the receiver’s rate would improve the performanceof such algorithms. Rate measurements over short time intervalscould allow fast detection of change in the rate observed bythe upper layers of a cellular receiver. However, for cellularreceivers, upper-layer rate measurements over short time scalesproduce unreliable results due to the effect of underlying lowerlayer mechanisms such as scheduling and retransmissions. In thispaper, we introduce a rate estimation approach that reduces thevariability observed in short time scale receiver rate measurementsand allows faster rate change detection. We also integratean adaptive mechanism to improve online measurements overdifferent time scales.

  • 325.
    Haile, Habtegebreil Kassaye
    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).
    Grinnemo, Karl-Johan
    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).
    Rate Change Detection in Stationary Cellular Nodes2019In: Proceedings of the Fifteenth Swedish National Computer NetworkingWorkshop (SNCNW), Luleå, Sweden. 4-5 June, 2019Conference paper (Refereed)
    Abstract [en]

    An increasing number of cellular congestion controlalgorithms (CCAs) are relying on measurements of the deliveryrate observed at the receiver. Accordingly, early detection ofchanges in the receiver’s rate would improve the performanceof such algorithms. Rate measurements over short time intervalscould allow fast detection of change in the rate observed bythe upper layers of a cellular receiver. However, upper layerrate measurements for cellular receivers over a short time scaleproduce unreliable results due to the effect of underlying lowerlayer mechanisms. In this paper, we introduce a rate estimationapproach that reduces the variability observed in short timescale receiver rate measurements and allows faster rate changedetection.

  • 326.
    Haile, Habtegebreil Kassaye
    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).
    Grinnemo, Karl-Johan
    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).
    Atxutegi Narbona, Eneko
    University of the Basque Country.
    Liberal, Fidel
    University of the Basque Country.
    Arvidsson, Åke
    Kristianstad University.
    Evaluation of the Impact of TCP BBR Startup on CUBIC Traffic2018In: The Fourteenth Swedish National Computer Networking Workshop (SNCNW) 2018, 2018Conference paper (Other academic)
  • 327.
    Halling, Sandra
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Identifiering av särbegåvade elever: Identifiering av generellt särbegåvade elever och särbegåvade elever inom ämnet matematik.2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The purpose of the study is to get the educators view on how they look upon their ability of identifying gifted pupils. If they feel that they have potential to be able to identify these pupils, or if they experience any hinders in their ability to identify them. I have chosen to use a survey to be able to get answers to my questions. The survey is sent to three small municipalities and I chose surveys instead of interviews because I wanted to have a wider distribution and several different kinds of educators answering.

    The study shows that many of the educators know the meaning of the concept of giftedness, but that they feel that they have lack knowledge on the subject.

  • 328.
    Hannesdottir, Emma
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    mAPPematik: Matematiskt innehåll i surfplattors appar för barn i yngre åldrar2014Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study is designed to study the apps that can be downloaded and used on surf tablets, as tablets become more common educational tools. This study focuses on reviewing apps that can be used in mathematics education for young learners. Surf tablets are more and more available in schools, as they are cheap and easy tools to use. Applications purchased or downloaded to the surf plates are cheap, easily accessible and there is a vast amount of them. However, the educational research on surf tablets and its applications are not as extensive.

    The study further discuss how the math applications can be used in mathematics education coupled with a clear goal and purpose of use. The skills and core content as the study focuses on are the students' ability to develop understanding and use of numbers, the meaning of the equal sign, the counting rules and the number axis.

    The study shows that all the 13 apps included in the survey can be used in mathematics education for skill training, but only in three of them are the descriptions so basic so that newly beginners can use them.

  • 329.
    Hansen, Marit
    et al.
    Unabhängiges Landeszentrum für Datenschutz (ULD), Kiel, Germany.
    Kosta, EleniTilburg Institute for Law, Technology and Society (TILT), Tilburg University, Tilburg, The Netherlands.Nai-Fovino, IgorEuropean Commission - Joint Research Centre, Ispra, Italy.Fischer-Hübner, SimoneKarlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Privacy and Identity Management: The Smart Revolution2018Conference proceedings (editor) (Refereed)
    Abstract [en]

    This book contains selected papers presented at the 12th IFIP WG 9.2, 9.5, 9.6/11.7, 11.6/SIG 9.2.2 International Summer School on Privacy and Identity Management, held in Ispra, Italy, in September 2017.The 12 revised full papers, 5 invited papers and 4 workshop papers included in this volume were carefully selected from a total of 48 submissions and were subject to a three-phase review process. The papers combine interdisciplinary approaches to bring together a host of perspectives: technical, legal, regulatory, socio-economic, social, societal, political, ethical, anthropological, philosophical, and psychological. They are organized in the following topical sections: privacy engineering; privacy in the era of the smart revolution; improving privacy and security in the era of smart environments; safeguarding personal data and mitigating risks; assistive robots; and mobility and privacy.

  • 330. Harrer, S.
    et al.
    Kopp, O.
    Lenhard, Jörg
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Patterns for workflow engine benchmarking2018In: ESOCC 2016: Advances in Service-Oriented and Cloud Computing / [ed] Barbosa, S.D.J., Filipe, J., Kotenko, I., Sivalingam, K.M., Washio, T., Yuan, J., Zhou, L., Springer , 2018, p. 151-163Conference paper (Refereed)
    Abstract [en]

    Workflow engines are frequently used in the service-oriented and cloud computing domains. Since engines have significant impact on the quality of service provided by hosted applications, it is desirable to compare and select the most appropriate engine for a given task. To enable such a comparison, approaches for benchmarking workflow engines have emerged. Although these approaches deal with different quality properties, such as performance or standard conformance, they face many reoccurring problems during the design and implementation phase, which they solve in similar ways. In this paper, we describe such common solutions to reoccurring problems in the area of workflow engine benchmarking as patterns. Our aim is to present pattern candidates that help benchmark authors to design and implement proper and valid workflow engine benchmarks and benchmarking tools

  • 331.
    Harrer, Simon
    et al.
    University of Bamberg.
    Kopp, Oliver
    University of Stuttgart.
    Lenhard, Jörg
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Patterns for workflow engine benchmarking2016Conference paper (Refereed)
  • 332.
    Harrer, Simon
    et al.
    University of Bamberg.
    Lenhard, Jörg
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013). Karlstad University.
    Kopp, Oliver
    University of Stuttgart.
    Ferme, Vincenzo
    USI Lugano.
    Pautasso, Cesare
    USI Lugano.
    A Pattern Language for Workflow Engine Conformance and Performance Benchmarking2017In: Proceedings of the 22nd European Conference on Pattern Languages of Programs EuroPLoP '17, Association for Computing Machinery (ACM), 2017, article id article No 1Conference paper (Refereed)
    Abstract [en]

    Workflow engines are frequently used in the domains of business process management, service orchestration, and cloud computing, where they serve as middleware platforms for integrated business applications. Engines have a significant impact on the quality of service provided by hosted applications. Therefore, it is desirable to compare them and to select the most appropriate engine for a given task. To enable such a comparison, approaches for benchmarking workflow engines have emerged. Although these approaches deal with different quality attributes, i.e., performance or standard conformance, they face many reoccurring design and implementation problems, which have been solved in similar ways. In this paper, we present a pattern language that captures such common solutions to reoccurring problems (e.g., from test identification, benchmarking procedure validation, automatic engine interaction, and workflow execution observation) in the area of workflow engine conformance and performance benchmarking. Our aim is to help future benchmark authors with the pattern language presented in this paper to benefit from our experience with the design and implementation of workflow engine benchmarks and benchmarking tools

  • 333. Hartswood, Mark
    et al.
    Jirotka, Marina
    Chenu-Abente, Ronald
    Hume, Alethia
    Giunchiglia, Fausto
    Martucci, Leonardo
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Fischer-Hübner, Simone
    Karlstad University, Division for Information Technology.
    Privacy for Peer Profiling in Collective Adaptive Systems2015In: Privacy and Identity Management for the Future Internet in the Age of Globalisation: 9th IFIP WG 9.2, 9.5, 9.6/11.7, 11.4, 11.6/SIG 9.2.2 International Summer School, Patras, Greece, September 7-12, 2014, Revised Selected Papers / [ed] Jan Camenisch, Simone Fischer-Hübner, Marit Hansen, Cham: Springer, 2015, p. 237-252Chapter in book (Refereed)
    Abstract [en]

    In this paper, we introduce a privacy-enhanced Peer Manager, which is a fundamental building block for the implementation of a privacy-preserving collective adaptive systems computing platform. The Peer Manager is a user-centered identity management platform that keeps information owned by a user private and is built upon an attribute-based privacy policy. Furthermore, this paper explores the ethical, privacy and social values aspects of collective adaptive systems and their extensive capacity to transform lives. We discuss the privacy, social and ethical issues around profiles and present their legal privacy requirements from the European legislation perspective.

  • 334.
    Hassan, Mahdi Mohammad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Afzal, Wasif
    Mälardalen University.
    Blom, Martin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Lindström, Birgitta
    University of Skövde.
    Andler, Sten
    University of Skövde.
    Eldh, Sigrid
    Ericsson AB.
    Testability and Software Robustness: A Systematic Literature Review2015In: 2015 41st Euromicro Conference on Software Engineering and Advanced Applications, IEEE, 2015, p. 341-348Conference paper (Refereed)
    Abstract [en]

    The concept of software testability has been researched in several different dimensions, however the relation of this important concept with other quality attributes is a grey area where existing evidence is scattered. The objective of this study is to present a state-of-the-art with respect to issues of importance concerning software testability and an important quality attribute: software robustness. The objective is achieved by conducting a systematic literature review (SLR) on the topic. Our results show that a variety of testability issues are in focus with observability and controllability issues being most researched. Fault tolerance, exception handling and handling external influence are prominent robustness issues in focus.

  • 335.
    Hassan, Mahdi Mohammad
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Afzal, Wasif
    Lindström, Birgitta
    Shah, Syed Muhammad Ali
    Andler, Sten F.
    Blom, Martin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Testability and software performance: A systematic mapping study2016In: SAC '16 Proceedings of the 31st Annual ACM Symposium on Applied Computing, Association for Computing Machinery (ACM), 2016, p. 1566-1569Conference paper (Refereed)
    Abstract [en]

    In most of the research on software testability, functionalcorrectness of the software has been the focus while the ev-idence regarding testability and non-functional propertiessuch as performance is sporadic. The objective of this studyis to present the current state-of-the-art related to issuesof importance, types and domains of software under test,types of research, contribution types and design evaluationmethods concerning testability and software performance.We nd that observability, controllability and testing e ortare the main testability issues while timeliness and responsetime (i.e., time constraints) are the main performance issuesin focus. The primary studies in the area use diverse types ofsoftware under test within di erent domains, with real-timesystems as being a dominant domain. The researchers haveproposed many di erent methods in the area, however thesemethods lack implementation in practice as suggested byour gures for research type, contribution type and designevaluation methods.

  • 336.
    Hasselström, Nicklas
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Hjern, Gunnar
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Hoorn, Richard
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Hult, Marcus
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Häger, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Syren, Jens
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Alfredsson, Stefan
    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.
    The Design, Implementation, and Performance Evaluation of Secure Socket SCTP 2.02015Report (Other academic)
    Abstract [en]

    The Stream Control Transmission Protocol (SCTP) is acomparatively new transport protocol that presents some advanced features compared to other standardized transport protocols. However, there are currently no standardized end-to-end security solutions suited for SCTP. One proposal for end-to-end encryption is the Secure Socket SCTP (S2-SCTP) protocol, developed by researchers at Karlstad University.  The security solution for SCTP described in this report uses key agreement for obtaining keys to be able to provide data confidentiality by encryption. The protocol is based on the S2-SCTP protocol, with smaller changes, and an overlaying management protocol has been designed and implemented. The management protocolis used to enable encryption and TLS authentication, to give a secure communication library over existing Berkeley Sockets. The performance evaluation of S2-SCTP compared to the already standardized end-to-endsecurity solutions, i.e., TLS over SCTP and DTLS over SCTP, shows that S2-SCTP achieves a higher throughput while still maintaining most of the advantages of SCTP.

  • 337.
    Hatamian, Majid
    et al.
    Goethe University Frankfurt, Frankfurt am Main, Germany.
    Kitkowska, Agnieszka
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Korunovska, Jana
    Vienna University of Business and Economics, Vienna, Austria.
    Kirrane, Sabrina
    Vienna University of Business and Economics, Vienna, Austria.
    “It’s shocking!": Analysing the impact and reactions to the A3: Android apps behaviour analyser2018In: Data and Applications Security and Privacy XXXII / [ed] Florian Kerschbaum, Stefano Paraboschi, Cham: Springer, 2018, p. 198-215Conference paper (Refereed)
    Abstract [en]

    The lack of privacy awareness in smartphone ecosystems prevents users from being able to compare apps in terms of privacy and from making informed privacy decisions. In this paper we analysed smartphone users’ privacy perceptions and concerns based on a novel privacy enhancing tool called Android Apps Behaviour Analyser (A3). The A3 tool enables user to behaviourally analyse the privacy aspects of their installed apps and notifies about potential privacy invasive activities. To examine the capabilities of A3 we designed a user study. We captured and contrasted privacy concern and perception of 52 participants, before and after using our tool. The results showed that A3 enables users to easily detect their smartphone app’s privacy violation activities. Further, we found that there is a significant difference between users’ privacy concern and expectation before and after using A3 and the majority of them were surprised to learn how often their installed apps access personal resources. Overall, we observed that the A3 tool was capable to influence the participants’ attitude towards protecting their privacy.

  • 338.
    Hatamian, Majid
    et al.
    Goethe University Frankfurt, Germany.
    Momen, Nurul
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Fritsch, Lothar
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Rannenberg, Kai
    Goethe University Frankfurt, Germany.
    A Multilateral Privacy Impact Analysis Method for Android Apps2019In: Privacy Technologies and Policy / [ed] M. Naldi, G. F. Italiano, K. Rannenberg, M. Medina & A. Bourka, Cham: Springer, 2019, Vol. 11498, p. 87-106Conference paper (Refereed)
    Abstract [en]

    Smartphone apps have the power to monitor most of people’s private lives. Apps can permeate private spaces, access and map social relationships, monitor whereabouts and chart people’s activities in digital and/or real world. We are therefore interested in how much information a particular app can and intends to retrieve in a smartphone. Privacy-friendliness of smartphone apps is typically measured based on single-source analyses, which in turn, does not provide a comprehensive measurement regarding the actual privacy risks of apps. This paper presents a multi-source method for privacy analysis and data extraction transparency of Android apps. We describe how we generate several data sets derived from privacy policies, app manifestos, user reviews and actual app profiling at run time. To evaluate our method, we present results from a case study carried out on ten popular fitness and exercise apps. Our results revealed interesting differences concerning the potential privacy impact of apps, with some of the apps in the test set violating critical privacy principles. The result of the case study shows large differences that can help make relevant app choices.

  • 339. Hein, Patrick
    et al.
    Biswas, Debmalya
    Martucci, Leonardo
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Mühlhäuser, Max
    Technische Universität Darmstadt.
    Conflict Detection and Lifecycle Management for Access Control in Publish/Subscribe Systems2011In: High-Assurance Systems Engineering (HASE), 2011 IEEE 13th International Symposium on, IEEE Press, 2011, p. 104-111Conference paper (Refereed)
    Abstract [en]

    In today's collaborative business environment there is a need to share information across organizational boundaries. Publish/Subscribe systems are ideal for such scenarios as they allow real-time information to be shared in an asynchronous fashion. In this work, we focus on the access control aspect. While access control in general for publish/subscribe systems has been studied before, their usage in a multi-organizational scenario leads to some novel challenges. Here a publisher might wish to enforce restrictions w.r.t. not only subscribers, but also other publishers publishing certain event types due to competitive or regulatory reasons. With different publishers and subscribers having their own preferences and restrictions, conflicts are evident w.r.t. both publishing and subscribing to specific event types. Given this, the first contribution of this work is to provide efficient conflict detection and resolution algorithms. The other important (and often ignored) aspect of large scale and evolving systems is that of efficiently handling modifications to existing policies, e.g. a rule may become invalid after a certain period of time. Our approach in handling such modifications is two-fold: (i) to maintain consistency and (ii) to automatically detect and enforce rules which could not have been enforced earlier due to conflicts. The second contribution of our work is thus to provide lifecycle management for access control rules, which is tightly coupled with the conflict detection and resolution algorithms.

  • 340.
    Hellberg, Jesper
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Jönsson, Petter
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    FångstDataBanken: En administrativ webbplats för Sportfiskarna2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Swedish Anglers Association (Sportfiskarna) collects statistics on fishing in Sweden for use in research and management. With the launch of applications for smart phones, the number of reported catches has increased and the need to manage data both to and from these applications has arisen. This dissertation describes the creation of Sportfiskarna’s website FångsDataBanken. The main purpose of the site is to administer the information provided in the mobile applications but also to deal with the reported catches for statistical purposes.

    The result of the project is a website written in ASP.NET MVC that satisfies the customer’s requirements. The site is the core of Sportfiskarna's system to manage the catch reporting and will become operational in the summer of 2015. 

  • 341.
    Hemdal, Tim
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    Hellberg, Adam
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science.
    EPIM Sync: Verifying information on inRiver and Episerver2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    When inRiver pushes to Episerver through a connector, there is no sure way to guarantee that all information is transferred without corruption. This project aims to create a service which pulls all product information from inRiver and Episerver and does a field by field comparison and creates a checksum for the values. The result of the comparison will be saved to a database and can be displayed graphically as a tree structure on a website. The project successfully achieved all the goals defined in the specification.

  • 342.
    Hemmi, Kirsti
    et al.
    Uppsala universitet, Åbo Akedemi University, Finland.
    Bråting, Kajsa
    Uppsala universitet.
    Liljekvist, Yvonne
    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), Department of Educational Studies (from 2013).
    Prytz, Johan
    Uppsala universitet.
    Madej, Lars
    Uppsala universitet.
    Pejlare, Johanna
    Chalmers University of Technology and the University of Gothenburg.
    Palm Kaplan, Kristina
    Uppsala universitet.
    Characterizing Swedish school algebra – initialfindings from analyses of steering documents,textbooks and teachers’ discourses2017In: Skrifter från Svensk förening för matematikdidaktisk forskning, ISSN 1651-3274, no 12, p. 299-308Article in journal (Refereed)
    Abstract [en]

    The paper reports the first results of an ongoing research project aiming atcharacterizing Swedish school algebra (grades 1-9). Both diachronic andsynchronic studies are conducted to identify the specific teaching traditiondeveloped in Sweden and different theoretical approaches are applied in theoverall project in order to obtain a rich picture of the Swedish case. The resultsreported here are based on the analyses of mathematics curriculum, textbooks andfocus group interviews with teachers in seven schools. The initial results indicatethat, since 1980s, algebra is vaguely addressed in the steering documents and theprogression of algebraic thinking is elusive in teachers’ discourses. We discuss theimplications of the initial findings for our project.

  • 343.
    Hemmi, Kirsti
    et al.
    Åbo Akademi University, Finland & Uppsala University, Sweden.
    Krzywacki, Heidi
    University of Helsinki, Finland & Mälardalen University, Sweden.
    Liljekvist, Yvonne
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Challenging traditional classroom practices: Swedish teachers’ interplay with Finnish curriculum materials2018In: Journal of Curriculum Studies, ISSN 0022-0272, E-ISSN 1366-5839, Vol. 51, no 3, p. 1-20Article in journal (Refereed)
    Abstract [en]

    In the current paper, we present an analysis of a case study in which we have followed Swedish primary teachers who voluntarily began using translated Finnish curriculum materials, i.e. a textbook and teacher guide, in order to reform their mathematics teaching. The multifaceted data, consisting of questionnaires, interviews, protocols from collegial meetings and classroom observations, were gathered during the period 2010–2014. The analysis of the interplay within this cross-cultural setting reveals the special characteristics and the challenges existing in practice. Both the experienced and inexperienced teachers offloaded a great deal of their agency to the materials in order to become familiar with the ideas they mediated. Yet, the lack of a clear rationale behind the organization of the materials, as well as the suggested activities connected to taken-for-granted features of the Finnish teaching tradition, made fruitful interaction problematic. The changes teachers made in their classroom practice were tightly connected to the support offered in the materials, without which the teachers abandoned their new classroom patterns. Based on the results of this study, we suggest a number of general aspects that we regard as important to consider when implementing curriculum materials developed within another cultural-educational context.

  • 344.
    Hernandez Benet, Cristian
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Alizadeh Noghani, Kyoomars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    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).
    Minimizing Live VM Migration Downtime Using OpenFlow based Resiliency Mechanisms2016In: Cloud Networking (Cloudnet), 2016 5th IEEE International Conference on, IEEE, 2016Conference paper (Refereed)
  • 345.
    Hernandez Benet, Cristian
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Alizadeh Noghani, Kyoomars
    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). Karlstad University, Faculty of Economic Sciences, Communication and IT, Centre for HumanIT.
    Dobrijevic, Ognjen
    University of Zagreb, Croatia.
    Jestin, Patrick
    Ericsson AB, Sweden.
    Policy-based routing and load balancing for EVPN-based data center interconnections2017In: Network Function Virtualization and Software Defined Networks (NFV-SDN), 2017 IEEE Conference on Network Function Virtualization and Software Defined Networks (NFV-SDN), IEEE, 2017Conference paper (Refereed)
    Abstract [en]

    The Ethernet VPN (EVPN) technology has emerged as a key solution for the interconnection of geo-distributed Data Centers (DCs) over provider-managed MPLS networks. Such interconnections need to satisfy service-level agreements, which can be achieved by enforcing Traffic Engineering (TE) policies. However, deploying an effective TE policy is challenging and complex. This stems from the fact that network administrators should have a detailed insight into the network status and protocol specifics. Software-Defined Networking (SDN) may facilitate both the policy definition and deployment based on its comprehensive network view and existing integration with DC management systems, such as OpenStack. This paper presents an SDN-based framework for policy-driven DC interconnections that are built around EVPN. The framework is designed to translate routing and other TE policies, which are defined for EVPN instances, into appropriate low-level network actions to meet the policy goals. A generic programming interface allows an SDN controller to load different TE strategies so as to implement the policy, without the need to hard-code it. Moreover, our evaluations illustrate how clients might benefit from specific TE strategies and what is their impact on network performance

  • 346.
    Hernandez Benet, Cristian
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Alizadeh Noghani, Kyoomars
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Taheri, Javid
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    SDN implementations and protocols2018In: Big Data and Software Defined Networks / [ed] Javid Taheri, IET Digital Library, 2018, 1, p. 27-48Chapter in book (Refereed)
    Abstract [en]

    This chapter begins by explaining the main SDN concepts with the focus on a SDN controller. It presents the most important aspects to consider when we desire to go from traditional network to a SDN networks. We present an in-depth analysis of the most commonly used and modern SDN controllers and analyse the main features, capabilities and requirements of one of the presented controllers. OpenFlow is the standard leading in the market allowing the management of the forwarding plane devices such as routers or switches. While there are other standards with the same aim, OpenFlow has secured a position in the market and has been expanded rapidly. Therefore, an analysis is presented on a different OpenFlow compatible device for the implementation of an SDN network. This study encompasses both software and hardware solutions along with the scope of implementation or use of these devices. This chapter ends up presenting a description of OpenFlow protocol alternatives, a more detailed description of OpenFlow and its components and other wellknown southbound protocols involved for the management and configuration of the devices.

  • 347.
    Hernandez Benet, Cristian
    et al.
    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).
    Benson, T.
    Brown University, United States.
    Pongracz, G.
    Networking Research - Ericsson, United States.
    MP-HULA: Multipath transport aware load balancing using programmable data planes2018In: NetCompute 2018 - Proceedings of the 2018 Morning Workshop on In-Network Computing, Part of SIGCOMM 2018, Association for Computing Machinery, Inc , 2018, p. 7-13Conference paper (Refereed)
    Abstract [en]

    Datacenter networks ofer a large degree of multipath in order to provide large bisectional bandwidth. The end-to-end performance is determined by the load-balancing strategy which needs to be designed to efectively manage congestion. Consequently, congestion aware load-balancing strategies such as CONGA or HULA have been designed. Recently, more and more applications that are hosted on cloud servers use multipath transport protocols such as MPTCP. However, in the presence of MPTCP, existing load-balancing schemes including ECMP, HULA or CONGA may lead to suboptimal forwarding decisions where multiple MPTCP subfows of one connection are pinned on the same bottleneck link. In this paper, we present MP-HULA, a transport layer multi-path aware load-balancing scheme using Programmable Data Planes. First, instead of tracking congestion information for the best path towards the destination, each MP-HULA switch tracks congestion information for the best-k paths to a destination through the neighbor switches. Second, we design MP-HULA using Programmable Data Planes, where each leaf switch can identify, using P4, which MPTCP subfow belongs to which connection. MP-HULA then load-balances diferent MPTCP subfows of a MPTCP connection on diferent next hops considering congestion state while aggregating bandwidth. Our evaluation shows that MP-HULA with MPTCP outperforms HULA in average flow completion time (2.1x at 50% load, 1.7x at 80% load).

  • 348.
    Hernandez Benet, Cristian
    et al.
    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).
    Zola, Enrica
    Univ Politecn Cataluna, C Jordi Girona 1-3, Barcelona, Spain..
    Predicting expected TCP throughput using genetic algorithm2016In: Computer Networks, ISSN 1389-1286, E-ISSN 1872-7069, Vol. 108, p. 307-322Article in journal (Refereed)
    Abstract [en]

    Predicting the expected throughput of TCP is important for several aspects such as e.g. determining handover criteria for future multihomed mobile nodes or determining the expected throughput of a given MPTCP subflow for load-balancing reasons. However, this is challenging due to time varying behavior of the underlying network characteristics. In this paper, we present a genetic-algorithm-based prediction model for estimating TCP throughput values. Our approach tries to find the best matching combination of mathematical functions that approximate a given time series that accounts for the TCP throughput samples using genetic algorithm. Based on collected historical datapoints about measured TCP throughput samples, our algorithm estimates expected throughput over time. We evaluate the quality of the prediction using different selection and diversity strategies for creating new chromosomes. Also, we explore the use of different fitness functions in order to evaluate the goodness of a chromosome. The goal is to show how different tuning on the genetic algorithm may have an impact on the prediction. Using extensive simulations over several TCP throughput traces, we find that the genetic algorithm successfully finds reasonable matching mathematical functions that allow to describe the TCP sampled throughput values with good fidelity. We also explore the effectiveness of predicting time series throughput samples for a given prediction horizon and estimate the prediction error and confidence. 

  • 349.
    Hernandez Benet, Cristian
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Nasim, Robayet
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Alizadeh Noghani, Kyoomars
    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).
    OpenStackEmu - A Cloud Testbed Combining Network Emulation with OpenStack and SDN2017In: Consumer Communications & Networking Conference (CCNC), 2017 14th IEEE Annual, IEEE, 2017, p. 566-568Conference paper (Refereed)
    Abstract [en]

    OpenStack has been widely acknowledged to be one of the most important open source cloud platforms. In order to perform experimentally driven research in the area of cloud and cloud networking, there is however a big gap, because most researchers do not have access to a large cloud deployment and cannot change networking or compute infrastructure in order to test their algorithms and protocols on a large-scale. We developed OpenStackEmu, which is to the best of our knowledge the first attempt that combines OpenStack infrastructure with a Software Defined Networking (SDN) based controller such as OpenDaylight and a large-scale network emulator CORE (Common Open Research Emulator). The OpenStack compute and control nodes are connected to the CORE emulation server using TUN/TAP interfaces that inject the control (e.g. for VM migration) and data (VM-to-VM traffic) packets into a customizable network topology that is emulated using configurable Open vSwitches using CORE emulator. Experimenters can define e.g. fat-tree or distributed data center topologies and study the behavior of real VMs and services in those VMs under different background loads and SDN routing policies. We integrated the data center traffic generator DCT2Gen that allows to generate realistic background traffic based on traces from real data centers. Experimenters can study the performance impact of different VM migration strategies or different routing and load balancing schemes on real VM and application performance using different emulated topologies. We believe that OpenStackEmu is an important tool for both the SDN and OpenStack community in order to evaluate the performance of novel algorithms and protocols in the area of cloud networking.

  • 350.
    Herold, Sebastian
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Blom, Martin
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Mathematics and Computer Science (from 2013).
    Buckley, Jim
    University of Limerick / Lero, Ireland.
    Evidence in Architecture Degradation and Consistency Checking Research: Preliminary Results from a Literature Review2016In: Proceeding ECSAW '16 Proccedings of the 10th European Conference on Software Architecture Workshops, Association for Computing Machinery (ACM), 2016Conference paper (Refereed)
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