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  • 1.
    Abbasi, Shirin
    et al.
    Islamic Azad University, Iran.
    Rahmani, Amir Masoud
    Islamic Azad University, Tehran, Iran; National Yunlin University of Science and Technology, Taiwan.
    Balador, Ali
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Sahafi, Amir
    Islamic Azad University, Iran.
    A fault-tolerant adaptive genetic algorithm for service scheduling in internet of vehicles2023Ingår i: Applied Soft Computing, ISSN 1568-4946, E-ISSN 1872-9681, Vol. 143, artikel-id 110413Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Over the years, a range of Internet of Vehicles services has emerged, along with improved quality parameters. However, the field still faces several limitations, including resource constraints and the time response requirement. This paper extracts cost, energy, processing power, service management, and resource allocation parameters. Mathematical equations are then defined based on these parameters. To simplify the process complexity and ensure scalability, we propose an algorithm that uses the genetic algorithm for fault and cost management during resource allocation to services. The main concept is to pick resources for services using a genetic algorithm. We discuss the processing and energy costs associated with this function, which is the algorithm's objective function and is created to optimize cost. Our approach goes beyond the conventional genetic algorithm in two stages. In the first step, services are prioritized, and resources are allocated in accordance with those priorities; in the second step, load balancing in message transmission paths is ensured, and message failures are avoided. The algorithm's performance is evaluated using various parameters, and it was shown to outperform other metaheuristic algorithms like the classic genetic algorithm, particle swarm, and mathematical models. Different scenarios with various nodes and service variables are defined in various system states, including fault occurrences to various percentages of 10, 20, and 30. To compare methods, we consider different parameters, the most significant being performance success rate. Moreover, the cost optimization has a good convergence after iterations, and the rate of improvement in the big scenario has slowed down after 150 iterations. Besides, it provides acceptable performance in response time for services.

  • 2.
    Abdollahporan, Farzad
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Vandermaesen, Elvira
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Evaluation of the Impacts of Meraki API on Network Delivery Automation2024Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    In today's ever-automating world, businesses are increasingly focused on optimizing network operations, including configuration, management, and troubleshooting. This study scrutinizes the comparison between manual and automated methodologies within the framework of the cloud-based Cisco Meraki platform. Our objective is to establish decisive criteria for identifying the most advantageous circumstances for automation, particularly in network configuration. To achieve this, we constructed a network consisting of three Meraki devices. Automation of network configuration was facilitated through the development of Python scripts leveraging the Meraki API library in conjunction with configuration files. The configuration files were constructed in various file formats–Excel, CSV, JSON, and YAML– in order to assess their impact on automation effectiveness. Moreover, manual configuration tasks were undertaken by three network technicians with varying levels of Meraki proficiency. A comprehensive series of tests, encompassing both automated and manual methods, was subsequently conducted, focusing on metrics such as execution time and keystroke count. Through meticulous analysis, we provided valuable insights into the effectiveness of automation in network configuration processes. Results demonstrated that the use of JSON files in the automation process yielded the shortest completion time and required the fewest keystrokes compared to other automation methods. Moreover, manual configuration via the Meraki dashboard GUI exhibited comparable efficiency to automation methods in networks with a small number of devices. Nonetheless, owing to the capacity to reuse configuration files with minor adjustments for similar setups, the true advantage of automation over manual configuration becomes apparent as the device count increases.

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  • 3.
    Adamsson, Maximilian
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Enehöjd, Pontus
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Ledarskap - Nu på Digital nivå: En studie om hur digital kommunikation bör utformas för att organisationer ska bli mer effektiva och ha ett bra kommunikationsflöde med mindre informationsbortfall.2020Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Digital kommunikation är idag självklart för de allra flesta människor, alla kommunicerar digitalt via olika sorters enheter och kanaler. Dock kommer den digitala kommunikationen i väldigt många olika former så kan det ibland bli svårt och komplext för alla att hantera denna sorts kommunikation. Denna studie har för avsikt att skapa ett underlag för en mer komplett och kontrollerbar kommunikation via digitala medel, samt hur ledarskap kan främjas via kommunikation i digital form. Detta ska bidra med en grundläggande kunskap kring hur en organisation bör hantera och förmedla sin information och kommunikation via digitala medel.

    Studien fokuserar på att skapa en förståelse för hur digital kommunikation upplevs av mottagaren. För att därifrån kunna se hur denna upplevelse kan föras närmare den fysiska kommunikationen mellan en ledare och medarbetare. I ett samarbete med Barn och utbildningsförvaltningen, en väldigt stor organisation med ansvar för all grundutbildning i Eskilstuna kommun, det vill säga allt från förskola upp till gymnasial utbildning. Denna organisation har analyserats genom en induktiv forskningsmetod med kvalitativa intervjuer, dessa har varit grunden för att samla in data. Genom dessa kvalitativa intervjuer samlas åsikter och tankar in från medlemmar av alla olika delar av organisationen för att skapa en heltäckande bild om hur den digitala kommunikationen upplevs och fungerar.

    Kunskapsbidragets syfte för denna uppsats var att få fram kunskap om hur en digital kommunikationsmiljö bör utformas för att organisationer ska bli mer effektiva, ha ett bra kommunikationsflöde samt mindre informationsbortfall. Detta syfte anses vara uppfyllt genom slutsatserna utifrån teori och empiriinsamling. Där en organisation med en bra struktur, organisationskunskap samt grundtanke har alla möjligheter att då utveckla sina ledare. Detta kan i sin tur utveckla medarbetare och därmed skapa en mer effektiv organisation, med bra och tydliga kanaler där alla är införstådda hur dem fungerar.

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  • 4.
    Alexander, Karlsson
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Design and Development of a Wireless Multipoint E-stop System for Autonomous Haulers2018Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Safety-related functions are important in autonomous industrial applications and are featured in an extensive body of work contained within the standards. The implementation of safety-related systems is commonly done by an external company at a great cost and with limited flexibility. Thus, the objective of this thesis was to develop and implement a safety-related system using o-the-shelf products and to analyse how well it can comply with the established standards of safety-related functions. This work has sought to review the current standards for safety-functions, the eectsof harsh radio environments on safety-related systems, and how to validate the safety-function.The system development process was used to gain knowledge by rst building the concept based on pre-study. After the pre-study was nished, the process moved to the development of software, designed to maintain a wireless heartbeat as well as to prevent collisions between the autonomous and manual-driven vehicles at a quarry, and implementation of the system in real hardware. Finally, a set of software (simulations) and hardware (measurements in an open-pit mine) tests were performed to test the functionality of the system. The wireless tests showed that the system adhered to the functional requirements set by the company, however, the evaluated performance level according to ISO 13849-1 resulted in performance level B which is insucient for a safety-related function. This work demonstrates that it is not possible to develop a safety-related system using the off-the-shelf products chosen, without hardware redundancy.

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  • 5.
    Alkamha, Saaid
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Ahmadi, Alireza
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Upptäckandet av säkerhetshot i privata nätverk: Hur du skyddar ditt hemnätverk2023Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    På grund av Covid 19 har de flesta människor valt att jobba hemifrån och de flesta hushåll har en accesspunkt som möjliggör kommunikation mellan flera enheter. Attacker mot Wi-Fi accesspunkter har ökat under de senaste åren på grund av sårbarheter som kan finnas i accesspunkten. När en sårbar väg hittas i accesspunkt kan detta ledda till att angriparen använder den sårbara vägen för att göra ett intrång och skada en eller flera enheter i hemnätverket och även företagens enheter. Teknikens framsteg har hjälpt oss att implementera flera säkerhetsåtgärder som kan skydda accesspunkten vid intrångsförsök. Syftet med detta arbete är att lägga fokus på att ge rätt kunskap för nya nätverkstekniker för att öka medvetenhet inom säkerheten i hemnätverk. Målet med detta examensarbete är att ge en djupare kunskap för nya nätverkstekniker för att kunna förhindra eller minimera attacker som orsakas av sårbarheter i ett hemnätverk med Wi-Fi accesspunkt och ta fram en rutin för hur det ska skyddas. Efter vi har identifierat en mängd attacker och själva utfört dem, visade resultatet att det var lätt att manipulera en sårbar accesspunkt med de valda attacksverktygen i detta arbete och experimenten har påvisat oss vikten av att implementera rätt säkerhetsåtgärder och hur väl de skyddar accesspunkten mot ett intrångsförsök.

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  • 6.
    Al-Rawi, Mohammed
    et al.
    Universidade de Aveiro, Portugal.
    Elmgren, Fredrik
    DeepVision AB, Linköping, Sweden.
    Frasheri, Mirgita
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Curuklu, Baran
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Yuan, Xin
    Universidad Politecnica de Madrid, Spain.
    Martínez, José-Fernán
    Universidad Politecnica de Madrid, Spain.
    Bastos, Joaquim
    Instituto de Telecomunicações - Pólo de Aveiro, Portugal.
    Rodriguez, Jonathan
    Universidade de Aveiro, Portugal.
    Pinto, Marc
    ECA Robotics, France.
    Algorithms for the Detection of First Bottom Returns and Objects in the Water Column in Side-Scan Sonar Images2017Ingår i: OCEANS '17 A Vision for our Marine Future OCEANS '17, Aberdeen, United Kingdom, 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    Underwater imaging has become an active research area in recent years as an effect of increased interest in underwater environments and is getting potential impact on the world economy, in what is called blue growth. Since sound propagates larger distances than electromagnetic waves underwater, sonar is typically used for underwater imaging. One interesting sonar image setting is comprised of using two parts (left and right) and is usually referred to as sidescan sonar. The image resulted from sidescan sonars, which is called waterfall image, usually has to distinctive parts, the water column and the image seabed. Therefore, the edge separating these two parts, which is called the first bottom return, is the real distance between the sonar and the seabed bottom (which is equivalent to sensor primary altitude). The sensory primary altitude can be measured if the imaging sonar is complemented by interferometric sonar, however, simple sonar systems have no way to measure the first bottom returns other than signal processing techniques. In this work, we propose two methods to detect the first bottom returns; the first is based on smoothing cubic spline regression and the second is based on a moving average filter to detect signal variations. The results of both methods are compared to the sensor primary altitude and have been successful in 22 images out of 25.

  • 7.
    Ashjaei, Mohammad
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Multi-Hop Real-Time Communication over Switched Ethernet Technology2014Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Switched Ethernet technology has been introduced to be exploited in real-time communication systems due to its features such as its high throughput and wide availability, hence being a cost-effective solution. Many real-time switched Ethernet protocols have been developed, preserving the profits of traditional Ethernet technology, to overcome the limitations imposed by using commercially available (COTS) switches. These limitations mainly originate from the non-deterministic behavior of the Ethernet switches inherent in the use of FIFO queues and a limited number of priority levels.

     

    In our research we focus on two particular real-time communication technologies, one based on COTS Ethernet switches named the FTT-SE architecture and the other using a modified Ethernet switch called the HaRTES architecture. Both architectures are based on a master-slave technique supporting different and temporally isolated traffic types including real-time periodic, real-time sporadic and non-real-time traffic. Also, they provide mechanisms implementing adaptivity as a response to the requirements imposed by dynamic real-time applications. Nevertheless, the two mentioned architectures were originally developed for a simple network consisting of a single switch, and they were lacking support for multi-hop communication. In industrial applications, multi-hop communication is essential as the networks comprise a high number of nodes, that is far beyond the capability of a single switch.

     

    In this thesis, we study the challenges of building multi-hop communication using the FTT-SE and the HaRTES architectures. We propose different architectures to provide multi-hop communication while preserving the key characteristics of the single-switch architecture such as timeliness guarantee, resource efficiency, adaptivity and dynamicity. We develop a response time analysis for each proposed architecture and we compare them to assess their corresponding benefits and limitations. Further, we develop a simulation tool to evaluate the solutions.

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  • 8.
    Avni, G.
    et al.
    IST Austria, Klosterneuburg, Austria.
    Goel, S.
    IIT Bombay, Mumbai, India.
    Henzinger, T. A.
    IST Austria, Klosterneuburg, Austria.
    Rodriguez-Navas, Guillermo
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Computing scores of forwarding schemes in switched networks with probabilistic faults2017Ingår i: Lecture Notes in Computer Science, Volume 10206, Springer Verlag , 2017, s. 169-187Konferensbidrag (Refereegranskat)
    Abstract [en]

    Time-triggered switched networks are a deterministic communication infrastructure used by real-time distributed embedded systems. Due to the criticality of the applications running over them, developers need to ensure that end-to-end communication is dependable and predictable. Traditional approaches assume static networks that are not flexible to changes caused by reconfigurations or, more importantly, faults, which are dealt with in the application using redundancy. We adopt the concept of handling faults in the switches from non-real-time networks while maintaining the required predictability. We study a class of forwarding schemes that can handle various types of failures. We consider probabilistic failures. For a given network with a forwarding scheme and a constant ℓ, we compute the score of the scheme, namely the probability (induced by faults) that at least ℓ messages arrive on time. We reduce the scoring problem to a reachability problem on a Markov chain with a “product-like” structure. Its special structure allows us to reason about it symbolically, and reduce the scoring problem to #SAT. Our solution is generic and can be adapted to different networks and other contexts. Also, we show the computational complexity of the scoring problem is #P-complete, and we study methods to estimate the score. We evaluate the effectiveness of our techniques with an implementation.

  • 9.
    Bajracharya, Rojeena
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Shrestha, Rakesh
    Res Inst Sweden RISE, S-72212 Västerås, Sweden..
    Hassan, Syed Ali
    Natl Univ Sci & Technol, Sch Elect Engn & Comp Sci, Islamabad 44000, Pakistan..
    Jung, Haejoon
    Kyung Hee Univ, Dept Elect & Informat Convergence Engn, Yongin 17104, South Korea..
    Shin, Hyundong
    Kyung Hee Univ, Dept Elect & Informat Convergence Engn, Yongin 17104, South Korea..
    5G and Beyond Private Military Communication: Trend, Requirements, Challenges and Enablers2023Ingår i: IEEE Access, E-ISSN 2169-3536, Vol. 11, s. 83996-84012Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Communication networks are becoming increasingly important in military operations, with task fields like time-critical targeting, covert special operations, command and control, training, and logistics, all relying heavily on the communication network and its services. On the other hand, commercial communication has dramatically transformed our society and the way we communicate. The newest network mode at present, 5G and beyond (5GB), is characterized by high speed, low latency, high reliability, and high communication density. Although the use of 5GB commercial networks for defense agencies can offer greater flexibility and efficiency, they also face a new challenge that requires high standards of network protection and harsh working conditions and environments. In this paper, we discuss the significance of communication networks in several potential military applications, particularly for warfare, training/drilling, logistics, and special mission-specific stations. We present the communication trends adopted in military applications. Then, we open up various 5GB key performance indexes and their use cases for the military communication systems. We also elaborate on unique challenges of the military communication networks that are unlikely to be resolved via commercial 5GB research. The various 5GB enabling technologies for military communication systems are discussed. Lastly, we present and analyze 5GB new radio for the private military communication under C-band.

  • 10.
    Barac, Filip
    et al.
    Mid Sweden University.
    Yu, Kan
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Gidlund, Mikael
    ABB, Corporate Research.
    Åkerberg, Johan
    ABB, Corporate Research.
    Björkman, Mats
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Towards Reliable and Lightweight Communication in Industrial Wireless Sensor Networks2012Konferensbidrag (Refereegranskat)
    Abstract [en]

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

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  • 11.
    Bergblomma, Marcus
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Ekström, Martin
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Björkman, Mats
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Ekström, Mikael
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Gerdtman, Christer
    Motion Control AB, Västerås, Sweden .
    Lindén, Maria
    Mälardalens högskola, Akademin för innovation, design och teknik.
    A wireless low latency control system for harsh environments2012Ingår i: IFAC Proceedings Volumes (IFAC-PapersOnline): Vol. 11, PART 1, 2012, s. 17-22Konferensbidrag (Refereegranskat)
    Abstract [en]

    The use of wireless communication technologies in the industry offer severaladvantages. One advantage is the ability to deploy sensors where they previously could noteasily be deployed, for instance on parts that rotate. To use wireless communication in industrialcontrol loops, demands on reliability and latency requirements has to be met. This in anenvironment that may be harsh for radio communication. This work presents a reliable, lowlatency wireless communication system. The system is used in a wireless thyristor control loopin a hydro power plant generator. The wireless communication is based on Bluetooth radiomodules. The work shows a latency analysis together with empirical hardware based latencyand packet error rate measurements. The background noise of a hydro power plant station isalso investigated. The average latency between the Bluetooth modules for the proposed systemis 5.09 ms. The packet error rate is 0.00288 for the wireless low latency control system deployedin a hydro power plant.

  • 12.
    Berglund, Anton
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Ayoub, Yousif
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Praktisk analys av vilken skyddsförmåga VLAN har mot cyberattacker i nätverk2024Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Nätverkssäkerheten har blivit viktigare än någonsin med tanke på de allt mer sofistikeradecyberattackerna. Bristande nätverkssäkerhet kan leda till förödande konsekvenser såsomdataförluster, läckage av konfidentiella dokument eller total systemnedgång. Det är en allmänfakta mellan nätverksingenjörer att VLAN är en teknik för att höja säkerheten i nätverk genomatt segmentera det. Men hur effektivt kan det skydda mot verkliga cyberattacker? Det härarbetet bidrar till att öka kunskapen om vilken förmåga VLAN har för att skydda mot olikacyberattacker. I arbetet används programvaran GNS3 för att bygga två likadana nätverk där enaär segmenterat med VLAN och andra är inte segmenterat. Nätverken bestod av bland annat tvåklientdatorer där ena var offret med operativsystemet Windows 10 och andra var angriparenmed Kali Linux. I nätverken fanns även en switch och en router. Med hjälp av verktygenEttercap, Dsniff och Hping3 utfördes attackerna ARP spoofing, MAC flooding och Pingflooding. Syftet med detta är att jämföra attackernas skadeeffekt med och utan VLAN.Resultaten visade att VLAN-tekniken kunde mildra skadeeffekterna mot Ping flooding,blockera ARP spoofing, men hade ingen effekt mot MAC flooding-attacken. Slutsatsen vikunde dra av arbetet är att VLAN kan vara ett bra skydd mot vissa typer av attacker, men äringet skydd mot andra. Därför bör nätverksingenjörer inte förlita sig enbart på VLAN somsäkerhetsåtgärd för sina nätverk.

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  • 13.
    Bergström, Albert
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Automatic generation of network configuration in simulated time sensitive networking (TSN) applications2020Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The amount of data required to be processed in real-time embedded system is steadily increasing. This has caused industries to search for alternatives for reliable time-sensitive network communication. IEEE set of standards for Time-Sensitive Networking (TSN) is an attractive option for achieving this. It leverages the advantages of IEEE standards for Ethernet, such as high bandwidth and low hardware cost, while introducing deterministic behaviour. Simulation tools are used to facilitate verification and analysis of TSN networks. However, even simulation-assisted design of large complex networks is a challenging process. To alleviate this issue, this thesis investigates how TSN simulation can be improved by automatic generation of network configurations. So far, many different simulation frameworks have been developed in academia. This thesis builds on the OMNeT++ simulation framework and NeSTiNg simulation model. We prototype an automatic TSN configuration tool capable of generating configuration automatically through a graphical user interface (GUI). The purpose of the prototype is to demonstrate the feasibility of automatic configuration in TSN and how it eases design complexity. Furthermore, to verify the proposed tool a use case inspired by the vehicle industry is modelled. It is concluded that automatic configuration improves usability in five key areas, such as: (1) facilitating recollection of the network, (2) enabling automatic configuration, (3) increasing user-friendliness of a TSN simulation platform with a GUI, (4) increasing efficiency and usability of a TSN simulation platform, and (5) minimizing user error. The results gained in this thesis justify the usability of automation and could provide insights for future research and development of TSN simulation tools.

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  • 14.
    Biabani, M.
    et al.
    School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, 14395 515, Iran.
    Yazdani, N.
    School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, 14395 515, Iran.
    Fotouhi, Hossein
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Developing a Novel Hierarchical VPLS Architecture Using Q-in-Q Tunneling in Router and Switch Design2023Ingår i: Computers, E-ISSN 2073-431X, Vol. 12, nr 9, artikel-id 180Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Virtual Private LAN Services (VPLS) is an ethernet-based Virtual Private Network (VPN) service that provides multipoint-to-multipoint Layer 2 VPN service, where each site is geographically dispersed across a Wide Area Network (WAN). The adaptability and scalability of VPLS are limited despite the fact that they provide a flexible solution for connecting geographically dispersed sites. Furthermore, the construction of tunnels connecting customer locations that are separated by great distances adds a substantial amount of latency to the user traffic transportation. To address these issues, a novel Hierarchical VPLS (H-VPLS) architecture has been developed using 802.1Q tunneling (also known as Q-in-Q) on high-speed and commodity routers to satisfy the additional requirements of new VPLS applications. The Vector Packet Processing (VPP) performs as the router’s data plane, and FRRouting (FRR), an open-source network routing software suite, acts as the router’s control plane. The router is designed to seamlessly forward VPLS packets using the Request For Comments (RFCs) 4762, 4446, 4447, 4448, and 4385 from The Internet Engineering Task Force (IETF) integrated with VPP. In addition, the Label Distribution Protocol (LDP) is used for Multi-Protocol Label Switching (MPLS) Pseudo-Wire (PW) signaling in FRR. The proposed mechanism has been implemented on a software-based router in the Linux environment and tested for its functionality, signaling, and control plane processes. The router is also implemented on commodity hardware for testing the functionality of VPLS in the real world. Finally, the analysis of the results verifies the efficiency of the proposed mechanism in terms of throughput, latency, and packet loss ratio.

  • 15.
    Blazek, Thomas
    et al.
    Silicon Austria Labs GmbH, Australia.
    Ademaj, Fjolla
    Silicon Austria Labs GmbH, Australia.
    Marksteiner, Stefan
    Mälardalens universitet. AVL List GmbH, Australia.
    Priller, Peter
    AVL List GmbH, Australia.
    Bernhard, Hans-Peter
    Silicon Austria Labs GmbH, Australia; Johannes Kepler University Linz, Australia.
    Wireless Security in Vehicular Ad Hoc Networks: A Survey2022Ingår i: SAE International Journal of Connected and Automated Vehicles, ISSN 2574-0741, Vol. 6, nr 2Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Vehicular communications face unique security issues in wireless communications. While new vehicles are equipped with a large set of communication technologies, product life cycles are long and software updates are not widespread. The result is a host of outdated and unpatched technologies being used on the street. This has especially severe security impacts because autonomous vehicles are pushing into the market, which will rely, at least partly, on the integrity of the provided information. We provide an overview of the currently deployed communication systems and their security weaknesses and features to collect and compare widely used security mechanisms. In this survey, we focus on technologies that work in an ad hoc manner. This includes Long-Term Evolution mode 4 (LTE-PC5), Wireless Access in Vehicular Environments (WAVE), Intelligent Transportation Systems at 5 Gigahertz (ITS-G5), and Bluetooth. First, we detail the underlying protocols and their architectural components. Then, we list security designs and concepts, as well as the currently known security flaws and exploits. Our overview shows the individual strengths and weaknesses of each protocol. This provides a path to interfacing separate protocols while being mindful of their respective limitations.

  • 16.
    Bujosa Mateu, Daniel
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Enhancing TSN Adoption by Industry: Tools to Support Migrating Ethernet-based Legacy Networks into TSN2023Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Uppfinningen av ångmaskinen i slutet av 1700-talet markerade början på en kontinuerlig och snabb process av automatisering och förbättring inom industrin, som tog ytterligare fart i och med införandet av datorstyrda maskiner och robotik i mitten av 1900-talet. Moderna fabriker och deras produkter är beroende av hundratals specialiserade processorer, inklusive sensorer, ställdon och styrenheter, som samarbetar för att utföra uppgifter och tillhandahålla tjänster. Dessa processorer är beroende av kommunikations-subsystem för att samordna och dela resurser. Dessa system, som vanligtvis kallas distribuerade system, omger oss och används av de flesta människor hela tiden. Exempel på distribuerade system finns i en mängd olika exempel, från moderna bilar till fabriker som producerar olika varor. I en bil finns det till exempel många olika sensorer och ställdon som hastighetsmätare, positionssensorer, bränsleinsprutare och tändspolar, som alla arbetar tillsammans för att se till att bilen fungerar säkert och effektivt, medan det i fabriker används robotarmar, transportband och andra anordningar för att automatisera produktionsprocessen och öka effektiviteten.

    Den snabba utvecklingen av tekniken kan dock göra det svårt för företag att hålla jämna steg med de senaste verktygen och systemen, eftersom kostnaden för att införa tekniken kanske inte är kostnadseffektiv, inte bara på grund av att tekniken måste förvärvas, utan också på grund av de förändringar som införandet kräver i andra system som samarbetar. Till exempel skulle införandet av ett nytt kommunikations-subsystem kräva att alla enheter som använder det anpassas. Dessutom kräver uppgraderingen till nyare teknik ofta betydande resurser, inte bara ekonomiska utan även naturresurser. Detta kan leda till ökat avfall och ökade koldioxidutsläpp, vilket utgör en risk för miljön. Dessutom kan följderna av teknikuppgraderingar, till exempel bortskaffande av föråldrad utrustning och produktion av e-avfall, ha ytterligare miljöpåverkan.

    I den här avhandlingen fokuserar vi på Time Sensitive Networking (TSN), en ny kommunikationsstandard med betydande fördelar för den framväxande tekniken. Även om TSN-tekniken ger många fördelar, bland annat högre kommunikationshastighet och lägre latenstider, saknar många nuvarande industrisystem mjuk- och hårdvarukraven för att stödja denna teknik. Målet med vår forskning är därför tvåfaldigt: för det första att förbättra TSN’s mekanismer för att göra den mer attraktiv för industrin och för det andra att utveckla verktyg som möjliggör en sömlös migration och integration av äldre system till TSN, så att slutstationerna kan utnyttja fördelarna med TSN utan att behöva byta ut eller uppgradera större delen av systemet. Detta tillvägagångssätt sparar värdefull tid och resurser och minskar det avfall som uppstår under processen.

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  • 17.
    Bujosa Mateu, Daniel
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Proenza, Julián
    University of the Balearic Islands, Spain.
    Papadopoulos, Alessandro
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Improved Clock Synchronization in TSN Networks with Legacy End-Stations2023Rapport (Övrigt vetenskapligt)
    Abstract [en]

    In order to enable the adoption of Time Sensitive Networking (TSN) by the industry and be more environmentally sustainable, it is necessary to develop tools to integrate legacy systems with TSN. In this paper, we propose a solution for the coexistence of different time domains from different legacy systems with their corresponding synchronization protocols in a single TSN network. To this end, we experimentally identified the effects of replacing the communications subsystem of a legacy Ethernet-based network with TSN in terms of synchronization. Based on the results, we propose a solution called TALESS (TSN with Legacy End-Stations Synchronization). TALESS is able to identify the drift between the TSN communications subsystem and the integrated legacy devices (end-stations) and modify the TSN schedule to adapt to the different time domains to avoid the effects of the lack of synchronization between them. We validate TALESS through both simulations and experiments on a prototype. Thereby we demonstrate that thanks to TALESS, legacy systems are able to synchronize through TSN and even improve features such as their reception jitter or their integrability with other legacy systems.

  • 18.
    Castellanos Ardila, Julieth Patricia
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Gallina, Barbara
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Towards Efficiently Checking Compliance Against Automotive Security and Safety Standards2017Ingår i: The 7th IEEE International Workshop on Software Certification WoSoCer 2017, 2017, s. 317-324Konferensbidrag (Refereegranskat)
    Abstract [en]

    The growing connectivity of the systems that we rely on e.g. transportation vehicles is pushing towards the introduction of new standards aimed at providing a baseline to address cybersecurity besides safety. If the interplay of the two normative spaces is not mastered, compliance management might become more time consuming and costly, preventing engineers from dedicating their energies to system engineering. In this paper, we build on top of previous work aimed at increasing efficiency and confidence in compliance management. More specifically, we contribute to building a terminological framework needed to enable the systematization of commonalities and variabilities within ISO 26262 and SAE J3061. Then, we focus our attention on the requirements for software design and implementation and we use defeasible logic to prove compliance. Based on the compliance checking results, we reveal reuse opportunities. Finally, we draw our conclusions and sketch future research directions.

  • 19.
    Cromnow, Hannes
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Wretman, Tony
    Mälardalens universitet, Akademin för innovation, design och teknik.
    MQTT och OPC UA för IIoT - En cybersäkerhetsanalys2024Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Industrial Internet of Things (IIoT) implementeras i snabb takt. Attackytan för cyberhot inom IIoT-nätverk har utvidgats i takt med en mer utbredd användning, och cybersäkerhet för IIoT-enheter har inte varit i fokus. Brister i att upprätthålla säkerhet kan resultera i allvarliga konsekvenser för företag genom bland annat produktionsavbrott, ekonomiska förluster och stöld av affärshemligheter. Arbetets syfte har varit att öka säkerheten för IIoT-nätverk genom att analysera MQTT och OPC UA ur ett säkerhetsperspektiv,  två kommunikationsprotokoll som förekommer inom IIoT-nätverk. Arbetet belyser hur olika nivåer av implementerad säkerhet för MQTT och OPC UA förhåller sig till upprätthållandet av konfidentialitet, riktighet och tillgänglighet.

    MITC AB är ett företag som bedriver samarbeten med Mälardalens Universitet och Mälardalens industri. MITC AB vill öka kunskapen för cybersäkerhet inom IIoT-nätverk och strävar efter att minska cyberhotens inverkan. Arbetet har innefattat litteraturstudier av tidigare arbeten inom området och egna experiment där vi utifrån olika scenarier har utfört cyberattacker mot IIoT-nätverk som implementerar MQTT och OPC UA. Experimentens resultat visade att det utan adekvat säkerhet är möjligt att med relativt enkla medel komma åt och manipulera data. Resultaten belyser också skillnader mellan MQTT och OPC UA ur ett säkerhetsperspektiv. Litteraturstudien tillsammans med experimenten har resulterat i en sammanställning av de åtgärder som krävs för att efterleva konfidentialitet, riktighet och tillgänglighet i IIoT-nätverk som implementerar MQTT eller OPC UA. Det här arbetet bidrar till att öka förståelsen för cybersäkerhet inom IIoT-nätverk, och kan fungera som underlag vid val av protokoll för implementering hos MITC AB och deras samarbetspartners.

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  • 20.
    Dao, Van-Lan
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Tran, Hung
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Girs, Svetlana
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Uhlemann, Elisabeth
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Reliability and Fairness for CANT Communication Based on Non-Orthogonal Multiple Access2019Ingår i: 2019 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS WORKSHOPS (ICC WORKSHOPS), IEEE , 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Recently, communication using unmanned aerial vehicles (LAVO as relay nodes has been considered beneficial for a number of applications. Moreover, nomorthogonM multiple access (NONIA) with users being assigned different signal passer levels while sharing the same tune-frequency domain has been found effective to enhance spectrum utilization and provide predictable access to the channel. Thus, in this paper we consider an UAV communication system with NOMA and propose a solution to find the optimal values for the user's power allocation coefficients (PA(s) needed to achieve the required levels of communication reliability. We present a closed-form expression for the PAC of each user and also propose an algori for finding the optimal altitude of the UAV required to satisfy the fairness condition for all users. Finally, we provide numerical mutinies and compare the results tar three types of communication environments.

  • 21.
    Deivard, Johannes
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Johansson, Valentin
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Diagnostics Framework for Time-Critical Control Systems in Cloud-Fog Automation2022Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Evolving technology in wireless telecommunication, such as 5G, provides opportunities to utilize wireless communication more in an industrial setting where reliability and predictability are of great concern. More capable Industrial Internet of Things devices (IIoT) are, indeed, a catalyst for Industry 4.0. Still, before the IIoT devices can be deemed capable enough, a method to evaluate the IIoT systems unobtrusively—so that the evaluation does not affect the performance of the systems—must be established. This thesis aims to answer how the performance of a distributed control system can be unobtrusively evaluated, and also determine what the state-of-the-art is in latency measurements in distributed control systems. To answer the question, a novel diagnostics method for time-critical control systems in cloud-fog automation is proposed and extensively evaluated on real-life testbeds that use 5G, WiFi 6, and Ethernet in an edge-computing topology with real control systems. The feasibility of the proposed method was verified by experiments conducted with a diagnostics framework prototype developed in this thesis. In the proposed diagnostics framework, the controller application is monitored by a computing probe based on an extended Berkeley Packet Filter program. Network communication between the controller and control target is evaluated with a multi-channel Ethernet probe and custom-made software that computes several metrics related to the performance of the distributed system. The data from the unobtrusive probes are sent to a time-series database that is used for further analysis and real-time visualization in a graphical interface created with Grafana. The proposed diagnostics method together with the developed prototype can be used as a research infrastructure for future evaluations of distributed control systems.

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  • 22.
    Dust, Lukas Johannes
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Persson, Emil
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Dynamic connection handling for scalable robotic systems using ROS22022Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Multi-agent robot systems, especially for mobile robots in dynamic environments interacting with humans, have seen an increased interest over the past years. Many vehicle manufactures (e.g.Volvo GTO) have been following the trend and has started investigating a possible implementation of an autonomous-transport robot system for material delivery in production environments.First implementations of a system have been built using ROS2 and initialising static amounts of participating robots.Throughout this thesis, scalability is emphasised to enhance and add new use cases to the system.This thesis investigates possible improvements for the system by adding a dynamic connection handling, which allows robots to connect and disconnect under the system's run time.Furthermore, the performance of the connection handling in the system is evaluated in simulation for increasing system complexity in terms of the amount of connected robots.The first part of the thesis presents an approach for the dynamic connection and disconnection of robots to the network using service client communication approaches.An implementation is tested in a simulation based on an excerpt from the legacy system.Furthermore, two methods are proposed for detecting possible communication losses. The thesis work simulates the increase of the number of robots in the system at different publishing rates. It compares a many to one communication approach, where multiple robots communicate to a central node over one topic, to the one to one communication approach, where multiple robots communicate over particular topics to a central node.The simulations have shown that with an increase of nodes, the average data age and the data miss ratio in the one to one approach were significantly lower than in the multi to one approach.

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  • 23.
    Feljan, Juraj
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Karapantelakis, A.
    Ericsson Research, Sweden.
    Mokrushin, L.
    Ericsson Research, Sweden.
    Inam, R.
    SOCNE, Sweden.
    Fersman, E.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Azevedo, C. R. B.
    University of Campinas, Brazil.
    Raizer, K.
    University of Campinas, Brazil.
    Souza, R. S.
    University of Campinas, Brazil.
    Tackling IoT complexity2017Ingår i: Ericsson Technology Review, ISSN 0014-0171, Vol. 95, nr 2, s. 60-69Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Internet of Things (IoT) applications transcend traditional telecom to include enterprise verticals such as transportation, healthcare, agriculture, energy and utilities. Given the vast number of devices and heterogeneity of the applications, both ICT infrastructure and IoT application providers face unprecedented complexity challenges in terms of volume, privacy, interoperability and intelligence. Cognitive automation will be crucial to overcoming the intelligence challenge.

  • 24.
    Fernandez, Z.
    et al.
    Information and Communication Technologies Area, Ikerlan Technology Research Centre, Mondragón, Spain.
    Val, I.
    Information and Communication Technologies Area, Ikerlan Technology Research Centre, Mondragón, Spain.
    Mendicute, M.
    Signal Theory and Communications Area, Mondragon University, Mondragón, Spain.
    Uhlemann, Elisabeth
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Analysis and Evaluation of Self-Organizing TDMA for Industrial Applications2019Ingår i: IEEE International Workshop on Factory Communication Systems - Proceedings, WFCS, Institute of Electrical and Electronics Engineers Inc. , 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    With the Industry 4.0 revolution, the inclusion of wireless communications with real-time requirements has been gaining popularity in industrial applications. As existing wireless technologies do not fully satisfy the stringent requirements of the most critical industrial applications, wired, centralized networks are often used. However, when the application requires mobility, there is no other way than to use wireless communications. Further, in applications where the topology changes dynamically and a large number of devices are mobile, centralized protocols are less suitable. Unfortunately, most decentralized medium access protocols are not predictable, and thereby not able to fulfil the real-time requirements. To address these challenges, in this paper Self-Organizing Time Division Multiple Access (STDMA) is analysed to assess its suitability for use in industrial applications. The analysis has been carried out through simulations under a multipath dispersed time-variant industrial channel while subject to a variable Doppler shift. To this end, several metrics such as channel access delay, slot occupation distribution (SOD), packet losses and packet inter-arrival time (PIAT) have been evaluated, using OMNeT++ in combination with the VEINS framework. 

  • 25.
    Fotouhi, Hossein
    et al.
    CISTER/INESC-TEC, ISEP, Polytechnic Institute of Porto, Portuga.
    Alves, Mário
    CISTER/INESC-TEC, ISEP, Polytechnic Institute of Porto, Portuga.
    Zuniga, Marco
    Delft University of Technology, The Netherlands.
    Koubâa, Anis
    CISTER/INESC-TEC, ISEP, Polytechnic Institute of Porto, Portuga.
    Reliable and fast hand-offs in low-power wireless networks2014Ingår i: IEEE Transactions on Mobile Computing, ISSN 1536-1233, E-ISSN 1558-0660, Vol. 13, nr 11, s. 2620-2633Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Hand-off (or hand-over), the process where mobile nodes select the best access point available to transfer data, has been well studied in wireless networks. The performance of a hand-off process depends on the specific characteristics of the wireless links. In the case of low-power wireless networks, hand-off decisions must be carefully taken by considering the unique properties of inexpensive low-power radios. This paper addresses the design, implementation and evaluation of smart-HOP, a hand-off mechanism tailored for low-power wireless networks. This work has three main contributions. First, it formulates the hard hand-off process for low-power networks (such as typical wireless sensor networks - WSNs) with a probabilistic model, to investigate the impact of the most relevant channel parameters through an analytical approach. Second, it confirms the probabilistic model through simulation and further elaborates on the impact of several hand-off parameters. Third, it fine-tunes the most relevant hand-off parameters via an extended set of experiments, in a realistic experimental scenario. The evaluation shows that smart-HOP performs well in the transitional region while achieving more than 98 percent relative delivery ratio and hand-off delays in the order of a few tens of a milliseconds.

  • 26.
    Fotouhi, Hossein
    et al.
    Polytechnic Institute of Porto (ISEP-IPP), Porto, Portugal.
    Zúñiga, Marco
    Polytechnic Institute of Porto (ISEP-IPP), Porto, Portugal.
    Alves, Mário
    Polytechnic Institute of Porto (ISEP-IPP), Porto, Portugal.
    Koubâa, Anis
    Polytechnic Institute of Porto (ISEP-IPP), Porto, Portugal.
    Marrón, Pedro
    Polytechnic Institute of Porto (ISEP-IPP), Porto, Portugal.
    Smart-HOP: A Reliable Handoff Mechanism for Mobile Wireless Sensor Networks2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Handoff processes, the events where mobile nodes select the best access point available to transfer data, have been well studied in cellular and WiFi networks. However, wireless sensor networks (WSN) pose a new set of challenges due to their simple low-power radio transceivers and constrained resources. This paper proposes smart-HOP, a handoff mechanism tailored for mobile WSN applications. This work provides two important contributions. First, it demonstrates the intrinsic relationship between handoffs and the transitional region. The evaluation shows that handoffs perform the best when operating in the transitional region, as opposed to operating in the more reliable connected region. Second, the results reveal that a proper fine tuning of the parameters, in the transitional region, can reduce handoff delays by two orders of magnitude, from seconds to tens of milliseconds.

  • 27.
    Girs, Svetlana
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Cooperative Communication for Increased Reliability in Industrial Wireless Networks2013Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Introducing wireless networks into distributed industrial systems may enable new or improved application areas and also great cost reductions due to lower complexity of installation and maintenance, compared to existing wired solutions. However, signals travelling through wireless channels are affected by pathloss, fading and shadowing, and, as a result, packet errors are both time-varying and more frequent than in e.g., existing wired fieldbuses. Packet errors or delays occurring in industrial systems can, in critical situations, lead to damage of expensive equipment or even danger to human life. Thus, wireless networks can be accepted for use in industrial networks only when sufficient levels of reliability and timeliness can be guaranteed.

    Relaying is a technique that has the potential to increase reliability with maintained delay. Having different geographical locations, and thus different wireless channel qualities, some nodes may overhear transmitted packets even in cases when the intended receiver did not, and then cooperate by relaying these packets to their final destination.

    This thesis deals with design of relaying strategies aiming to increase reliability in deadline-constrained industrial applications using wireless networks. The influence of several different parameters, such as positions of relay nodes, number of erroneous packets at the relay node and at the destination respectively, as well as the number of available time slots before the deadline, are evaluated to determine the best acting strategy for each relay node. Moreover, it is shown that when a specific relay node has the opportunity to aid more than one source node, performance can be improved even further if the relay node combines several packets, using Luby coding or packet aggregation, and instead relays such combined packets. Given the methods proposed in this thesis, the reliability in industrial wireless networks can be enhanced considerably, without increasing the delay, such that message deadlines still are kept.

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  • 28.
    Girs, Svetlana
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Bergblomma, Marcus
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Uhlemann, Elisabeth
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Halmstad University, Sweden.
    Štimac, Barbara
    University of Zagreb, Zagreb, Croatia .
    Björkman, Mats
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Design of Channel Measurement Guidelines for Characterization of Wireless Industrial Environments2013Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Providing reliable and timely communication in wireless industrial systems requires careful design of error control schemes able to tackle the bit error patterns typically occurring in these environments. As most error control schemes target some specific characteristics of a wireless channel, the selection of channel model is crucial for proper performance assessment. There are a number of widely used channel models, but the question of the most appropriate choice of model for industrial environments still remains largely open. Not many indoor measurement campaigns have focused on industrial environments with their own specific characteristics. In this paper we present a set of measurement guidelines aiming to characterize industrial environments such that suitable channel models can be selected to properly evaluate error control schemes targeting reliable and timely wireless communications in industrial environments. 

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  • 29.
    Girs, Svetlana
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Uhlemann, Elisabeth
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Halmstad University.
    Björkman, Mats
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Increased Reliability of Reduced Delay in Wireless Industrial Networks Using Relaying and Luby Codes2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    Providing reliable and timely communication in wireless industrial networks is crucial. Previous research has shown that relaying can aid in achieving this goal. We consider the case when relay resources are sparse such that each relay needs to aid e.g., three different sensor nodes and propose to combine relaying with Luby codes. We let the relay node construct a Luby coded packet using the three source packets as input. The destination can then use the Luby coded packet to recover an erroneous or lost source packet regardless of which source that packet belonged to. The performance evaluation shows that our proposed scheme significantly increases the number of correctly received packets before the corresponding deadlines, or alternatively that high reliability can be maintained even if fewer time slots are allocated for retransmissions, thus lowering the delay.

  • 30.
    Girs, Svetlana
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Uhlemann, Elisabeth
    Halmstad University.
    Björkman, Mats
    Mälardalens högskola, Akademin för innovation, design och teknik.
    The Effects of Relay Behavior and Position in Wireless Industrial Networks2012Ingår i: 2012 9th IEEE International Workshop on Factory Communication Systems, May 21-24, 2012 Lemgo, Germany: Proceedings, 2012, s. 183-190Konferensbidrag (Refereegranskat)
    Abstract [en]

    In wireless industrial networks, providing reliable and timely communication is crucial. Previous research has shown that relaying can be used to achieve this goal. However, we have found that different types of wireless channels encountered in industrial environments affect the benefits as well as the best behavior and position of relay nodes. We consider two types of behavior: the relay node always retransmits or it only retransmits if it has obtained a correct copy of the packet. We evaluate different positions of the relay node by conducting simulations for two types of fading channels: with and without line of sight. The results clearly show that the benefits, the best behavior and position of a relay node depends on the wireless channel, whether or not the bit errors appear randomly or in bursts and also on the distance between the source and the final destination.

  • 31.
    Girs, Svetlana
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Willig, Andreas
    University of Canterbury, Canterbury, New Zealand.
    Uhlemann, Elisabeth
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Halmstad University, Halmstad, Sweden.
    Björkman, Mats
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    On the Role of Feedback for Industrial Networks Using Relaying and Packet Aggregation2013Rapport (Övrigt vetenskapligt)
    Abstract [en]

    To be accepted for use in industrial applications, wireless technologies must offer similar performance in terms of reliability and timeliness as provided by current wired solutions. Wireless channels, introducing time-varying packet error rates, impose a significant challenge to fulfill these requirements. One way to improve reliability in industrial wireless networks is to use relaying, whereas packet aggregation is a method that can reduce delay. Hence, in this paper, we propose to use a combination of relaying and packet aggregation. Based on the type of feedback provided by the controller, the relay node can choose the most suitable way to use its allocated time slots such that more packets can reach the controller before their deadlines. The results show that allowing this kind of flexibility at the relay node results in performance improvements. The more flexibility, the greater the gain, and thus further improvements can be made by adjusting the schedule to take different types of feedback into account.

  • 32.
    Gran, Mikael
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Karlsson, Claes
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Survey of VMware NSX Virtualized Network Platform: Utvärdering av VMware NSX Virtualized Network Platform2017Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Atea Eskilstuna hade behovet av en plattform som kan förenkla och minska antalet konfigurationer vid implementation av kunder. Arbetet gick ut på att utvärdera plattformen VMware NSX och jämföra det mot traditionella nätverkslösningar. I dagens datacenter är virtualisering en viktig del av dess verksamhet. Användandet av virtualisering optimerar hanteringen av hårdvaru-resurser och kostnader. Virtualisering har hittills främst fokuserat på hantering av servrar och klienter, vilket har passerat nätverksutvecklingen, och därför har det uppstått vissa problem med traditionella datacenter gällande trafikflöden, säkerhet och implementering. Datacenter har tidigare varit optimerade för trafik som ska in eller ut ur datacentret. Detta har lett till att brandväggar och säkerhetspolicies ofta placerats vid datacentrets kant. I dagens datacenter har det däremot blivit en ökning på trafik mellan enheter inom datacentret som behöver skyddas. Denna typ av interna säkerhet kan uppnås av interna policies på samtliga nätverksenheter, dock blir det ohållbart vid implementation då antalet konfigurationspunkter i nätverket ökar. Dessa problem kan hanteras med hjälp av VMware NSX som virtualiserar nätverksenheter och centraliserar administration. NSX har en distribuerad brandväggs-funktion vilket medför att policies kan appliceras direkt på virtuella maskiner och virtuella routrar, från en central konfigurationspunkt. Detta ökar säkerheten och minskar implementationstiden jämfört med traditionella datacenter. Arbetet fokuserar på hur NSX arbetar till skillnad från fysiska nätverksenheter samt hur NSX hanterar frågor som trafikflöden, säkerhet och automation. För dessa ändamål byggdes en laborationsmiljö i Ravellos molntjänst med flertalet virtuella maskiner och en litteraturstudie utfördes. Laborationsmiljön användes för att sätta upp kunder med hjälp av virtuella nätverksenheter och virtuella maskiner. Laborationsmiljön användes som referens för hur implementation av NSX och dess funktioner går till. Litteraturstudien fokuserar på vad som är möjligt i NSX och vilka för- och nackdelar som finns med NSX jämfört med traditionella datacenter. Resultaten visade på att den enda nackdelen med NSX var dess licenskostnader.

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  • 33.
    Grankvist, Henrik
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Kvarnström, William
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Security Feature Test for Ethernet Switches2014Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    A new standard in network security for industrial control systems is about to be released by a number of working groups within the ISA99 organization. ABB has a certification program for network components that may be used together with the control system 800xA, which is named Industrial IT Certification. ABB now wants to introduce formal testing of network component’s security features according to this standard.The document IEC 62443-4-2 is the document within this standard that describes how the system requirements should be implemented on network components. This document is still a draft, so the document IEC 62443-3-3 which describes how the system requirements should be implemented on a whole industrial control system has been used to estimate the content of IEC 62443-4-2 when it is finished. Out of these two documents the requirements has been broken down into a test description which contains a number of tests to check which security features a switch has and that they work as described. Together with the test description, a test record template has been created to be used for documenting the result from the tests.Finally a comparison was made where the results from a number of different network equipment could be compared against each other regarding their security features. This comparison will in the future make it easier for ABB’s customers when they are in the process of buying new network equipment.In short the more expensive brands of switches have in general more security features implemented, and desktop switches has more security features implemented than industrial switches, with certain exceptions. The buyer needs to ask himself if he really needs all the security features. The choice of what switch to buy all depends on the placement of the switch and what purpose it should fulfill.

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    Thesis_HenrikGrankvist_WilliamKvarnstrom
  • 34.
    Gutiérrez, Marina
    et al.
    TTTech Computertechnik AG, Austria.
    Steiner, Wilfried
    TTTech Computertechnik AG, Austria.
    Dobrin, Radu
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Punnekkat, Sasikumar
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    A Configuration Agent based on the Time Triggered Paradigm for Real-Time Networks2015Ingår i: IEEE International Workshop on Factory Communication Systems - Proceedings, WFCS, 2015, Vol. Article number 7160584Konferensbidrag (Refereegranskat)
    Abstract [en]

    Distributed cyber-physical systems are growing in size and functionality and deterministic communication is an important requirement for those systems. The existing solutions based on the time-triggered paradigm pose certain limitations in regards to the configuration. Usually configuration is seen as a one-time event during the installation of the network. Future realtime networks need to be able to adapt more easily to changes in the network. Thus, the configuration becomes an ongoing service, e.g., as for network maintenance and re-configuration to add and remove new, respectively old, equipment. We postulate that configuration will emerge to a continued service that accompanies a real-time network throughout its different life-cycle phases. In this context of evolving and dynamic networks, we introduce the concept of a configuration agent for real-time networks and demonstrate the concept by a realization based on the time triggered paradigm.

  • 35.
    Gyllhamn, Claes
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Centraliserad styrning av åtkomstlistor2011Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Can the Danish "Aftalesystemet", a system with the intention to simplify the use of services within health care, be used in Sweden? This project has investigated the possibility by installing and testing the system and explored its functions to detect any eventual problems. Analyses were made of the system's graphical part and the underlying code to see in greater detail how the communication between units occurred, since no actual documentation of it existed. Discussions with the developers took place regarding how the current system works and how further development should continue. In order to test the system, a completely virtual environment was used. Server, clients and routers were virtualized with VirtualBox and GNS3 in order to not disrupt any ongoing services. The results show that because of how the Danish infrastructure is constructed, and how the system is developed to function primarily in a Danish infrastructure, some changes are needed regarding the design of the database, the GUI and the generation of access lists. Because MedCom and Inera are cooperating on this project, some functions will only be available in either language. However, the plan is that the system will be generalized to such a degree in the future that it can be used cooperatively by several countries.

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    centraliserad styrning av åtkomstlistor
  • 36.
    Haq, M. U.
    et al.
    Department of Computer System Engineering, University of Engineering and Technology, Peshawar, 25120, Pakistan.
    Sethi, M. A. J.
    Department of Computer System Engineering, University of Engineering and Technology, Peshawar, 25120, Pakistan.
    Rehman, Atiq Ur
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Capsule Network with Its Limitation, Modification, and Applications—A Survey2023Ingår i: Machine Learning and Knowledge Extraction, ISSN 2504-4990, Vol. 5, nr 3, s. 891-921Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Numerous advancements in various fields, including pattern recognition and image classification, have been made thanks to modern computer vision and machine learning methods. The capsule network is one of the advanced machine learning algorithms that encodes features based on their hierarchical relationships. Basically, a capsule network is a type of neural network that performs inverse graphics to represent the object in different parts and view the existing relationship between these parts, unlike CNNs, which lose most of the evidence related to spatial location and requires lots of training data. So, we present a comparative review of various capsule network architectures used in various applications. The paper’s main contribution is that it summarizes and explains the significant current published capsule network architectures with their advantages, limitations, modifications, and applications. 

  • 37.
    Hasan, Shahriar
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Fail-Operational and Fail-Safe Vehicle Platooningin the Presence of Transient Communication Errors2022Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Recent advances in wireless technology facilitating Vehicle-to-Vehicle (V2V)communication has paved the way towards a more connected and Cooperative-Intelligent Transportation System (C-ITS). It has unveiled the possibility of many services which are anticipated to make the road transport eco system safer, cleaner, and more sustainable. Platooning is one such application that is expected to soon appear on the roads. In platooning, a group of connected and highly automated vehicles follow a lead vehicle with short inter-vehicle distances. They adapt their speed, acceleration, steering angle, etc., with the help of on-board sensors and inter-vehicle communications. Due to the highly automated driving and the very short inter-vehicle distances required to achieve fuel-efficiency, platooning is a complex and safety-critical system of systems. As a result, the consequences of component or system failure can endanger human life, cause damage to property, or the environment. Given that V2V communication is subject to packet losses due to interference, path loss, fading and shadowing, it is usually desirable to maintain a sufficient level of platooning functionality without compromising safety also during periods of transient errors. Moreover, a platoon can experience different sensor failures, permanent hardware/software failures, or a suddenly appearing road hazard,e.g., a moose. The platoon should, therefore, also be capable of dissolving and transitioning into a fail-safe state by performing emergency braking, safestop, or manual handover without causing any harm to the equipment, people, or to the environment. This research work focuses on incorporating fail-operational mechanisms in platooning in a fuel-efficient and safe way, even inthe presence of transient errors and enable transition into a fail-safe state inthe event of an emergency. To this end, a platoon runtime manager is proposed, which monitors the channel quality and keeps the platoon operational in cases of temporal failures by degrading the platoon performance to the level at which it will remain acceptably safe. Simulation results demonstrate that the runtime manager can avoid collisions in the platoon and still maintain fair performance in terms of fuel-efficiency by either adjusting the inter-vehicle distances or switching to a different controller during runtime. Furthermore, two emergency braking strategies, namely Synchronized Braking and Adaptive Emergency Braking, are proposed to address the emergency events that can arise while platooning. These braking strategies are compared to several state-of-the-art braking strategies in terms of their ability to avoid collisions, and the distance traversed by the lead vehicle. Simulation results show that Synchronized Braking and Adaptive Emergency Braking strategies can ensure fail-safe platooning while the other braking strategies fail to do so. Moreover, a simulation tool named PlatoonSAFE has been developed to facilitate the evaluation of fail-operational and fail-safe mechanisms in platooning under realistic traffic, vehicle dynamics, and communication scenarios. 

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  • 38.
    Hasan, Shahriar
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Girs, Svetlana
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Uhlemann, Elisabeth
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Cooperative Automated Emergency Braking for CAVs under Time-Varying Communication Delays2023Ingår i: IAVVC 2023 - IEEE International Automated Vehicle Validation Conference, Proceedings, Institute of Electrical and Electronics Engineers Inc. , 2023Konferensbidrag (Refereegranskat)
    Abstract [en]

    Connected and Automated Vehicles (CAVs) have the potential to significantly improve road safety, fuel efficiency, and traffic flow by forming platoons with short inter-vehicle gaps, enabled by vehicle-to-vehicle communications and onboard sensors. However, wireless connectivity for CAVs is subject to time-varying delays, which can significantly impact platoon safety during emergency braking. To this end, this paper evaluates the communication delays incurred by platoon vehicles during emergency braking under various data and traffic densities. Additionally, an emergency braking strategy named adaptive emergency braking is proposed and compared with five other strategies based on their ability to meet the functional requirements of collision avoidance and minimizing the stopping distance of the platoon lead vehicle, which are crucial for transitioning a platoon to a fail-safe state. Moreover, the emergency braking strategies are evaluated through rigorous simulations, considering non-functional criteria such as required inter-vehicle gaps, maximum allowable deceleration rates, and their robustness under time-varying communication delays. 

  • 39.
    Henriksson, Johannes
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Magnusson, Alexander
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Impact of using cloud-based SDNcontrollers on the networkperformance2019Självständigt arbete på grundnivå (högskoleexamen), 180 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Software-Defined Networking (SDN) is a network architecture that differs from traditionalnetwork planes. SDN has tree layers: infrastructure, controller, and application. Thegoal of SDN is to simplify management of larger networks by centralizing control into thecontroller layer instead of having it in the infrastructure. Given the known advantages ofSDN networks, and the flexibility of cloud computing. We are interested if this combinationof SDN and cloud services affects network performance, and what affect the cloud providersphysical location have on the network performance. These points are important whenSDN becomes more popular in enterprise networks. This seems like a logical next step inSDN, centralizing branch networks into one cloud-based SDN controller. These questionswere created with a literature studies and answered with an experimentation method. Theexperiments consist of two network topologies both locally hosted SDN (baseline) and cloudhosted SDN. The topology used Zodiac FX switches and Linux hosts. The following metricswas measured: throughput, latency, jitter, packet loss, and time to add new hosts. Theconclusion is that SDN as a cloud service is possible and does not significantly affect networkperformance. One limitation with this thesis was the hardware, resulting in big fluctuationin throughput and packet loss.

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  • 40.
    Hoang, Le-Nam
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Uhlemann, Elisabeth
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Jonsson, M.
    School of Information Technology, Halmstad University, Halmstad, Sweden.
    Relay Grouping to Guarantee Timeliness and Reliability in Wireless Networks2019Ingår i: IEEE Communications Letters, ISSN 1089-7798, E-ISSN 1558-2558, Vol. 23, nr 9, s. 1661-1664, artikel-id 8737952Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Relaying can increase reliability, range, or throughput. In many cyber-physical systems (CPS), relaying is used to maximize reliability before a given deadline. Since concurrent transmissions are not supported by most CPS, time-division multiple access (TDMA) is typically used. However, a major drawback of relaying in TDMA is that pre-allocated time-slots are wasted if their respective transmitters do not have any correctly received packet to relay. Therefore, in this letter, we propose a novel relay grouping scheme to overcome this drawback. Numerical results show that the proposed scheme significantly enhances the reliability while guaranteeing the deadline for each message. 

  • 41.
    Holmstedt, Christoffer
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Model-checked Space Plug-and-Play Architecture Local Subnet Adaptation implemented in Ada with Ravenscar restrictions2014Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Space Plug-and-Play Architecture (SPA) is a set of standards to make it easier to build small satellites. Focus is put on improving the integration phase andthe time consuming validation and verification process by introducing plug-and-play functionality. From mission call-up to operational satellite it should only take six days.

    A SPA network consists of several different types of subnets with differentpros and cons. For each processing node there must be one Local Subnet Manager (SM-L). The SM-L can communicate over different communication protocols depending on how the respective local subnet is set up, one option is UDP/IP.

    In this thesis Ada Protected Objects is presented as a viable option for inter-process communication instead of UDP/IP in a SPA network. This thesis presents the initial work towards a SPA Local Subnet Adaptation that builds onlanguage constructs in Ada such as Ada Tasks and Protected Objects. The system design and implementation is verified deadlock free with UPPAAL but showsindications of livelock possibilities. The severity of these livelocksituations is discussed in the conclusion.

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    20141102_christoffer_holmstedt_master_thesis_679ea779
  • 42.
    Kailayanathan, Subaharan
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Kamdod, Saji
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Development of Generic Communication Middleware for Embedded Sensor Systems Transmitting Health Parameters2020Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Health technology or e-Health is one of the most rapidly growing areas in healthcare today and it has been an important requirement as a new concept of healthcare industry. Since global society has been changed to aging society and the healthcare cost has been increasing in the 21st century since 2007. As the total number of people aged 65 or older is expected to increase from 12% to 22% in 2050 which is double the rate, and at the same time there is a decrease in in-fertility rates and increase in life expectancy due to the increase in life quality, there is a need to investigate the needs and requirements of an intelligent embedded sensor systems in health applications, and to develop a new communication protocol or set of protocols that can be used to send data collected from a hub within a house, home-care or a complex and send it securely and reliably to a central database where the gathered data can be monitored by a medical professional to make decisions for further interventions. The employed communication protocol should also be able to securely transmit confidential parameters from the hospital network to a central server outside of the hospital network. The final protocol must be inline with the regulations of the EU. This thesis is done in collaboration with Tjeders AB, Stille AB, and Embedded Sensor Systems for Health Plus (ESS-H+) research profile at Mälardalen University. In this thesis, different communication protocols such as IPSec and TLS and algorithms such as AES and RSA are examined and based on the requirements provided by the companies certain of these protocols and algorithms will be used in the final implementation. Different performance metrics such as overhead, round trip delay and throughput will be measured for the chosen communication protocols and recommendations will be given on which of the protocols and algorithms needs to be used to obtain an optimized, secure and reliable network.

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  • 43.
    Karlsson, Marcus
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Zaja, Oscar
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Improving Security In Embedded Systems With IEEE 802.1X2021Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
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    fulltext
  • 44.
    Kiran, P.
    et al.
    Vidyavardhaka College of Engineering, India.
    Gururaj, H. L.
    Manipal Academy of Higher Education, India.
    Flammini, Francesco
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Sunil Kumar, D. S.
    Administrative Management College, India.
    Veeraprathap, V.
    Alva’s Institute of Engineering and Technology, India.
    Machine learning based 64-QAM classification techniques for enhanced optical communication2023Ingår i: Optical and quantum electronics, ISSN 0306-8919, E-ISSN 1572-817X, Vol. 55, nr 13, artikel-id 1179Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Due to their greatly increased spectrum efficiency, high-order quadrature amplitude modulation (QAM) formats are especially successful at increasing transmission capacity. QAM is extremely sensitive to nonlinear distortion because of its dense constellation and SNR-hungry configuration. Autonomous neural network (ANN) derived nonlinear decision boundaries that are adaptively created by machine learning techniques can be used to classify symbols. The proposed work focusing on the quadrature amplitude modulation (QAM) scheme, the approach is to formulate an autonomous neural network (ANN) that can predict the class of each symbol from a signal stream of symbols. Experimental accuracy for each ANN's of proposed work achieves 89% by analysing all tests. Comprehensive results are presented with comparisons, demonstrating notable nonlinear mitigation with BER reductions. Additionally, it offers a glimpse into potential future research plans intended to raise the likelihood that predictions would come true and their accuracy.

  • 45.
    Lavassani, Mehrzad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system. Rise - Research Institutes of Sweden, Sweden.
    Evolving Industrial Networks: Data-Driven Network Traffic Modelling and Monitoring2023Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The concept of Industrial IoT encompasses the joint applicability of operation and information technologies to expand the efficiency expectation of automation to green and flexible processes with innovative products and services. Future industrial networks need to accommodate, manage and guarantee the performance of converged traffic from different technologies. The network infrastructures are transforming to enable data availability for advanced applications and enhance flexibility. Nonetheless, the pace of IT–OT networks development has been slow despite their considered benefits in optimising performance and enhancing information flows. The hindering factors vary from general challenges in performance management of the diverse traffic for greenfield configuration to the lack of outlines for evolving from brownfield installations without interrupting the operation of ongoing processes. One tangible gap is the lack of insight into the brownfield installation in operation. This dissertation explores the possible evolutionary steps from brownfield installations to future industrial networks.The goal is to ensure the uninterrupted performance of brownfield installations on the path of evolving to the envisioned smart factories. It addresses the gap between the state of the art and state of practice, and the technical prerequisites of the integrated traffic classes for the development of an IIoT monitoring mechanism. A novel lightweight learning algorithm at the sensor level for an IIoT compliance monitoring system, together with a case study of traffic collected from a brownfield installation, provides the baseline of comparative analysis between the common assumptions and the state of practice. The identified gaps and challenges to address them directs the research for proposing a two-step aggregated traffic modelling by introducing new measurement method and performance indicator parameters for capturing the communication dynamics. Lastly, the sensor-level learning algorithm is refined with the knowledge gained from practice and research contributions to propose an in-band telemetry mechanism for monitoring aggregated network traffic.

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  • 46.
    Lavassani, Mehrzad
    et al.
    Department of Information and Communication Systems, IKS, Mid Sweden University, Sweden.
    Barac, Filip
    Department of Information and Communication Systems, IKS, Mid Sweden University, Sweden.
    Gidlund, Mikael
    Department of Information and Communication Systems, IKS, Mid Sweden University, Sweden.
    Zhang, Tingting
    Department of Information and Communication Systems, IKS, Mid Sweden University, Sweden.
    Handling event-triggered traffic of safety and closed-loop control systems in WSANs2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    This work investigates various methods to expand the deployment of Wireless Sensor-Actuator Networks (WSANs) to mission critical applications. We address the neglected open issues of hard deadline and deterministic delivery for event-triggered traffic in safety and closed-loop regulatory systems. DeMAC algorithm is proposed by utilizing TDMA-based subslots in emergency access periods, group acknowledgement, alternative packet structure, and relay node. The proposed algorithm displayed promising results in comparison with contention-based methods, in improving delivery rate of critical data within the deadline, and lowering the worst-case delay

  • 47.
    Lavassani, Mehrzad
    et al.
    Mid Sweden University, Sweden.
    Forsström, Stefan
    Mid Sweden University, Sweden.
    Jennehag, Ulf
    Mid Sweden University, Sweden.
    Zhang, Tingting
    Mid Sweden University, Sweden.
    Combining Fog Computing with Sensor Mote Machine Learning for Industrial IoT2018Ingår i: Sensors, E-ISSN 1424-8220, Vol. 18, nr 5, artikel-id 1532Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Digitalization is a global trend becoming ever more important to our connected and sustainable society. This trend also affects industry where the Industrial Internet of Things is an important part, and there is a need to conserve spectrum as well as energy when communicating data to a fog or cloud back-end system. In this paper we investigate the benefits of fog computing by proposing a novel distributed learning model on the sensor device and simulating the data stream in the fog, instead of transmitting all raw sensor values to the cloud back-end. To save energy and to communicate as few packets as possible, the updated parameters of the learned model at the sensor device are communicated in longer time intervals to a fog computing system. The proposed framework is implemented and tested in a real world testbed in order to make quantitative measurements and evaluate the system. Our results show that the proposed model can achieve a 98% decrease in the number of packets sent over the wireless link, and the fog node can still simulate the data stream with an acceptable accuracy of 97%. We also observe an end-to-end delay of 180 ms in our proposed three-layer framework. Hence, the framework shows that a combination of fog and cloud computing with a distributed data modeling at the sensor device for wireless sensor networks can be beneficial for Industrial Internet of Things applications.

  • 48.
    Lavassani, Mehrzad
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system. Research Institutes of Sweden, Industrial Systems, Sundsvall, Sweden.
    Åkerberg, Johan
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Björkman, Mats
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Data-driven Method for In-band Network Telemetry Monitoring of Aggregated Traffic2022Konferensbidrag (Refereegranskat)
    Abstract [en]

    Under the vision of industry 4.0, industrial networks are expected to accommodate a large amount of aggregated traffic of both operation and information technologies to enable the integration of innovative services and new applications. In this respect, guaranteeing the uninterrupted operation of the installed systems is an indisputable condition for network management. Network measurement and performance monitoring of the underlying communication states can provide invaluable insight for safeguarding the system performance by estimating required and available resources for flexible integration without risking network interruption or degrading network performance. In this work, we propose a data-driven in-band telemetry method to monitor the aggregated traffic of the network at the switch level. The method learns and models the communication states by local network-level measurement of communication intensity. The approximated model parameters provide information for network management for prognostic purposes and congestion avoidance resource planning when integrating new applications. Applying the method also addresses the consequence of telemetry data overhead on QoS since the transmission of telemetry packets can be done based on the current state of the network. The monitoring at the switch level is a step towards the Network-AI for future industrial networks.

  • 49.
    Lavassani, Mehrzad
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system. Division of Industrial Systems, RISE-Research Institutes of Sweden, Sweden.
    Åkerberg, Johan
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Björkman, Mats
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    From brown-field to future industrial networks, a case study2021Ingår i: Applied Sciences, E-ISSN 2076-3417, Vol. 11, nr 7, artikel-id 3231Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The network infrastructures in the future industrial networks need to accommodate, manage and guarantee performance to meet the converged Internet technology (IT) and operational technology (OT) traffics requirements. The pace of IT-OT networks development has been slow despite their considered benefits in optimizing the performance and enhancing information flows. The hindering factors vary from general challenges in performance management of the diverse traffic for green-field configuration to lack of outlines for evolving from brown-fields to the converged network. Focusing on the brown-field, this study provides additional insight into a brown-field characteristic to set a baseline that enables the subsequent step development towards the future’s expected converged networks. The case study highlights differences between real-world network behavior and the common assumptions for analyzing the network traffic covered in the literature. Considering the unsatisfactory performance of the existing methods for characterization of brownfield traffic, a performance and dynamics mixture measurement is proposed. The proposed method takes both IT and OT traffic into consideration and reduces the complexity, and consequently improves the flexibility, of performance and configuration management of the brown-field.

  • 50.
    Lavassani, Mehrzad
    et al.
    Division of Industrial Systems, RISE—Research Institutes of Sweden, Sundsvall, Sweden.
    Åkerberg, Johan
    Björkman, Mats
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Modeling and Profiling of Aggregated Industrial Network Traffic2022Ingår i: Applied Sciences, E-ISSN 2076-3417, Vol. 12, nr 2, artikel-id 667Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The industrial network infrastructures are transforming to a horizontal architecture to enable data availability for advanced applications and enhance flexibility for integrating new tech-nologies. The uninterrupted operation of the legacy systems needs to be ensured by safeguarding their requirements in network configuration and resource management. Network traffic modeling is essential in understanding the ongoing communication for resource estimation and configuration management. The presented work proposes a two-step approach for modeling aggregated traffic classes of brownfield installation. It first detects the repeated work-cycles and then aims to identify the operational states to profile their characteristics. The performance and influence of the approach are evaluated and validated in two experimental setups with data collected from an industrial plant in operation. The comparative results show that the proposed method successfully captures the temporal and spatial dynamics of the network traffic for characterization of various communication states in the operational work-cycles. 

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