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  • 1.
    Abdi, Somayeh
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Cognitive and Time Predictable Task Scheduling in Edge-cloud Federation2022Ingår i: IEEE International Conference on Emerging Technologies and Factory Automation, ETFA, Institute of Electrical and Electronics Engineers Inc. , 2022, Vol. 2022-SeptemberKonferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we present a hierarchical model for time predictable task scheduling in edge-cloud computing architecture for industrial cyber-physical systems. Regarding the scheduling problem, we also investigate the common problem-solving approaches and discuss our preliminary plan to realize the proposed architecture. Furthermore, an Integer linear programming (ILP) model is proposed for task scheduling problem in the cloud layer. The model considers timing and security requirements of applications and the objective is to minimize the financial cost of their execution.

  • 2.
    Abdi, Somayeh
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Task Offloading in Edge-cloud Computing using a Q-Learning Algorithm2024Ingår i: International Conference on Cloud Computing and Services Science, CLOSER - Proceedings, Science and Technology Publications, Lda , 2024, s. 159-166Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Task offloading is a prominent problem in edge−cloud computing, as it aims to utilize the limited capacityof fog servers and cloud resources to satisfy the QoS requirements of tasks, such as meeting their deadlines.This paper formulates the task offloading problem as a nonlinear mathematical programming model to maximizethe number of independent IoT tasks that meet their deadlines and to minimize the deadline violationtime of tasks that cannot meet their deadlines. This paper proposes two Q-learning algorithms to solve theformulated problem. The performance of the proposed algorithms is experimentally evaluated with respect toseveral algorithms. The evaluation results demonstrate that the proposed Q-learning algorithms perform wellin meeting task deadlines and reducing the total deadline violation time.

  • 3.
    Afshar, Sara Zargari
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Koroorian, Fereidon
    ABB, Västerås, Sweden.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Granlund, Anna
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Investigating Alternatives for System Architectures to Enhance Discrete Manufacturing2019Ingår i: International Journal of Distributed Sensor Networks, ISSN 1550-1329, E-ISSN 1550-1477, Vol. 15, nr 8, artikel-id 1550147719868668Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This article investigates the possibility of advancing discrete manufacturing using system architectures that are developed for Collaborative Process Automation Systems. Collaborative Process Automation System is a technology that has the potential to achieve production excellence for process industry. However, not much attention has been paid on using the architectures based on Collaborative Process Automation Systems for discrete manufacturing domains. In this article, we propose a base architecture consisting of three layers, and we discuss various alternatives to make the communications among the layers. We consider legacy components in the proposal, in contrast to most of the related works. In order to show the practicality of the proposed alternatives, we present an example that has been implemented in an ongoing project at ABB Robotics in Sweden.

  • 4.
    Agerskans, Natalie
    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.
    Bruch, Jessica
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Chirumalla, Koteshwar
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Critical Factors for Selecting and Integrating Digital Technologies to Enable Smart Production: A Data Value Chain Perspective2023Ingår i: IFIP Advances in Information and Communication Technology, Springer Science and Business Media Deutschland GmbH , 2023, s. 311-325Konferensbidrag (Refereegranskat)
    Abstract [en]

    With the development towards Industry 5.0, manufacturing companies are developing towards Smart Production, i.e., using data as a resource to interconnect the elements in the production system to learn and adapt accordingly for a more resource-efficient and sustainable production. This requires selecting and integrating digital technologies for the entire data lifecycle, also referred to as the data value chain. However, manufacturing companies are facing many challenges related to building data value chains to achieve the desired benefits of Smart Production. Therefore, the purpose of this paper is to identify and analyze the critical factors of selecting and integrating digital technologies for efficiently benefiting data value chains for Smart Production. This paper employed a qualitative-based multiple case study design involving manufacturing companies within different industries and of different sizes. The paper also analyses two Smart Production cases in detail by mapping the data flow using a technology selection and integration framework to propose solutions to the existing challenges. By analyzing the two in-depth studies and additionally two reference cases, 13 themes of critical factors for selecting and integrating digital technologies were identified.

  • 5.
    Agerskans, Natalie
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Bruch, Jessica
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Chirumalla, Koteshwar
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Ashjaei, Mohammad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Enabling Smart Production: The Role of Data Value Chain2022Ingår i: Advances in Production Management Systems. Smart Manufacturing and Logistics Systems: Turning Ideas into Action: IFIP WG 5.7 International Conference, APMS 2022, Gyeongju, South Korea, September 25–29, 2022, Proceedings, Part II / [ed] Duck Young Kim; Gregor von Cieminski; David Romero, Springer Science and Business Media Deutschland GmbH , 2022, Vol. 664, s. 477-485Konferensbidrag (Refereegranskat)
    Abstract [en]

    To stay competitive, manufacturing companies are developing towards Smart Production which requires the use of digital technologies. However, there is a lack of guidance supporting manufacturing companies in selecting and integrating a combination of suitable digital technologies, which is required for Smart Production. To address this gap, the purpose of this paper is twofold: (i) to identify the main challenges of selecting and integrating digital technologies for Smart Production, and (ii) to propose a holistic concept to support manufacturing companies in mitigating identified challenges in order to select and integrate a combination of digital technologies for Smart Production. This is accomplished by using a qualitative-based multiple case study design. This paper identifies current challenges related to selection and integration of digital technologies. To overcome these challenges and achieve Smart production, the concept of data value chain was proposed, i.e., a holistic approach to systematically map and improve data flows within the production system. © 2022, IFIP International Federation for Information Processing.

  • 6.
    Aglianò, Simone
    et al.
    University of Catania, Catania, Italy.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Lo Bello, Lucia
    University of Catania, Catania, Italy.
    Resource Management and Control in Virtualized SDN Networks2018Ingår i: CSI International Symposium on Real-Time and Embedded Systems and Technologies REST'18, 2018, s. 47-53Konferensbidrag (Refereegranskat)
    Abstract [en]

    Software defined networking and network virtual-ization are widely considered promising techniques for reducing the complexity of network management in many contexts that require high Quality of Service (QoS) and the support for heterogeneous architectures. In this paper we address a network architecture, here called a virtualized SDN network, that combines the benefits of SDN and virtualization. To cope with the demand for efficiently sharing a platform among several services, here a resource management mechanism to reserve and control network resources among various services in the virtualized SDN networks is proposed. The mechanism is implemented on an SDN controller and a set of experiments show the effectiveness of the proposed approach.

  • 7.
    Al-Dulaimy, Auday
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system. Dalarna University, Falun, Sweden.
    Ashjaei, Seyed Mohammad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Papadopoulos, Alessandro
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Fault Tolerance in Cloud Manufacturing: An Overview2023Ingår i: Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST, vol 495, Springer Science and Business Media Deutschland GmbH , 2023, s. 89-101Konferensbidrag (Refereegranskat)
    Abstract [en]

    Utilizing edge and cloud computing to empower the profitability of manufacturing is drastically increasing in modern industries. As a result of that, several challenges have raised over the years that essentially require urgent attention. Among these, coping with different faults in edge and cloud computing and recovering from permanent and temporary faults became prominent issues to be solved. In this paper, we focus on the challenges of applying fault tolerance techniques on edge and cloud computing in the context of manufacturing and we investigate the current state of the proposed approaches by categorizing them into several groups. Moreover, we identify critical gaps in the research domain as open research directions. 

  • 8.
    Al-Dulaimy, Auday
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Sicari, Christian
    University of Messina, Italy.
    Papadopoulos, Alessandro
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Galletta, Antonino
    University of Messina, Italy.
    Villari, Massimo
    University of Messina, Italy.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    TOLERANCER: A fault tolerance approach for cloud manufacturing environments2022Ingår i: IEEE International Conference on Emerging Technologies and Factory Automation, ETFA, Institute of Electrical and Electronics Engineers Inc. , 2022, Vol. 2022-SeptemberKonferensbidrag (Refereegranskat)
    Abstract [en]

    The paper presents an approach to solve the software and hardware related failures in edge-cloud environments, more precisely, in cloud manufacturing environments. The proposed approach, called TOLERANCER, is composed of distributed components that continuously interact in a peer to peer fashion. Such interaction aims to detect stress situations or node failures, and accordingly, TOLERANCER makes decisions to avoid or solve any potential system failures. The efficacy of the proposed approach is validated through a set of experiments, and the performance evaluation shows that it responds effectively to different faults scenarios.

  • 9.
    Alvarez Vadillo, Ines
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Bujosa Mateu, Daniel
    Mälardalens universitet, Akademin för innovation, design och teknik, Innovation och produktrealisering.
    Johansson, B.
    ABB, Västerås, Sweden.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Centralised Architecture for the Automatic Self-Configuration of Industrial Networks2023Ingår i: IEEE Int. Conf. Emerging Technol. Factory Autom., ETFA, Institute of Electrical and Electronics Engineers Inc. , 2023Konferensbidrag (Refereegranskat)
    Abstract [en]

    Novel production paradigms aim at increasing the efficiency and flexibility of production systems. Nonetheless, traditional industrial infrastructures lack the mechanisms needed to support these new paradigms. One of the main limiting factors is the architecture, which follows the automation pyramid in which subsystems are divided in layers depending on their functionalities. This allowed to meet the timing and dependability requirements of the production subsystems, however at the cost of limiting the exchange of information required to provide increased flexibility to the system. For this reason, in this paper we propose a new industrial architecture with a single network infrastructure to connect all the devices that conform to the industrial systems. On top of that, we design an Automatic Network Configurator to support the automatic configuration of the system. To assess the feasibility of our design and evaluate its performance, we implement the first instance of the architecture capable of supporting changes in the traffic requirements during run-time, i.e., without stopping or disrupting the system's operation. Furthermore, we use the implemented instance to measure the time required for reconfigurations.

  • 10.
    Alvarez Vadillo, Ines
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Servera, Andreu
    Universitat de les Illes Balears, Balears, Spain.
    Proenza, Julian
    Universitat de les Illes Balears, Balears, Spain.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Implementing a First CNC for Scheduling and Configuring TSN Networks2022Ingår i: IEEE International Conference on Emerging Technologies and Factory Automation, ETFA, Institute of Electrical and Electronics Engineers Inc. , 2022, Vol. 2022-SeptemberKonferensbidrag (Refereegranskat)
    Abstract [en]

    Novel industrial applications are leading to important changes in industrial systems. One of the most important changes is the need for systems that are capable to adapt to changes in the environment or the system itself. Because of their nature many of these applications are distributed, and their network infrastructure is key to guarantee the correct operation of the overall system. Furthermore, in order for a distributed system to be able to adapt, its network must be flexible enough to support changes in the traffic during runtime. The Time-Sensitive Networking (TSN) Task Group has proposed a series of standards that aim at providing deterministic real-time communications over Ethernet. TSN also provides centralised online configuration and control architectures which enable the online configuration of the network. A key part in TSN's centralised architectures is the Centralised Network Configuration element (CNC). In this work we present a first implementation of a CNC capable of scheduling time-triggered traffic and deploying such configuration in the network using the Network Configuration (NETCONF) protocol. We also assess the correctness of our implementation using an industrial use case provided by Volvo Construction Equipment.

  • 11.
    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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  • 12.
    Ashjaei, Mohammad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Real-Time Communication over Switched Ethernet with Resource Reservation2016Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Due to the need for advanced computer-controlled functionality in distributed embedded systems the requirements on network communication are becoming overly intricate. This dissertation targets the requirements that are concerned with real-time guarantees, run-time adaptation, resource utilization and flexibility during the development. The Flexible Time-Triggered Switched Ethernet (FTT-SE) and Hard Real-Time Ethernet Switching (HaRTES) network architectures have emerged as two promising solutions that can cater for these requirements. However, these architectures do not support multi-hop communication as they are originally developed for single-switch networks. This dissertation presents a fundamental contribution in multi-hop real-time communication over the FTT-SE and HaRTES architectures targeting the above mentioned requirements. It proposes and evaluates various solutions for scheduling and forwarding the traffic through multiple switches in these architectures. These solutions preserve the ability of dynamic adaptation without jeopardizing real-time properties of the architectures. Moreover, the dissertation presents schedulability analyses for the timeliness verification and evaluation of the proposed solutions as well as several protocols to support run-time adaptation in the multi-hop communication. Finally, the work led to an end-to-end resource reservation framework, based on the proposed multi-hop architectures, to support flexibility during the development of the systems. The efficiency of the proposed solutions is evaluated on various case studies that are inspired from industrial systems.

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  • 13.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Almeida, Luis
    University of Porto, Portugal.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    MTU Assignment in a Master-Slave Switched Ethernet Network2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we investigate the problem of selecting the Maximal Transmission Unit (MTU) size that maximizes the schedulability of real-time messages. We focus on a bandwidth-efficient master-slave switched Ethernet protocol, namely the FTT-SE protocol. We propose an algorithm to find the MTU for each message in order to maximize the schedulability of the messages. Moreover, we evaluate our proposed algorithm and we show that setting the MTU for messages using the algorithm increases the schedulability of messages compared with assigning the MTU to the maximum value that the protocol can support.

  • 14.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Almeida, Luis
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. University of Porto, Porto, Portugal .
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    MTU Configuration for Real-Time Switched Ethernet Networks2016Ingår i: Journal of systems architecture, ISSN 1383-7621, E-ISSN 1873-6165, Vol. 70, s. 15-25Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper, we show that in real-time switched Ethernet networks reducing the Maximum Transmission Unit (MTU) size may cause an increase or decrease in the response time of messages. This contradicting behavior arises an optimization problem for configuring the MTU size. We formulate the optimization problem in the context of the multi-hop HaRTES architecture, which is a hard real-time Ethernet protocol. As part of the solution, we propose a search-based algorithm to achieve optimum solutions. We modify the algorithm by presenting two techniques to reduce the search space. Then, we propose a heuristic algorithm with a pseudo-polynomial time complexity based on the search-based algorithm. We perform several experiments, and we show that the proposed heuristic results in an improvement regarding messages response times, compared with configuring the MTU to the maximum or minimum values. Moreover, we show in small network configurations that the heuristic performs as good as the search-based algorithm in many cases.

  • 15.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Almeida, Luis
    University of Porto, Portugal.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Performance Analysis of Master-Slave Multi-Hop Switched Ethernet Networks2013Ingår i: Proceedings of the 8th IEEE International Symposium on Industrial Embedded Systems, SIES 2013, 2013, s. 280-289Konferensbidrag (Refereegranskat)
    Abstract [en]

    There is an increasing trend towards using switched Ethernet in real-time distributed systems due to features like absence of collisions and high throughput. Nevertheless, a few problems persist, in particular related to priority inversion and limited length in queues. In this paper we focus on a protocol which uses a master-slave technique over standard switched Ethernet in order to overcome such problems, namely FTT-SE protocol. We present an improved response time analysis for such a network and we compare, analytically and with simulations, the results achieved with Network Calculus on a worst-case scenario. We show that our proposed response time analysis gives tighter bounds compared to Network Calculus. Moreover, we compare the performance of different solutions to scale the FTT-SE protocol with respect to the bandwidth utilization. Finally, we propose a new architecture to improve the average performance of master-slave switched Ethernet networks.

  • 16.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Malardalen Univ, Malardalen Real Time Res Ctr MRTC, POB 883, SE-72123 Vasteras, Sweden..
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Malardalen Univ, Malardalen Real Time Res Ctr MRTC, POB 883, SE-72123 Vasteras, Sweden..
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Malardalen Univ, Malardalen Real Time Res Ctr MRTC, POB 883, SE-72123 Vasteras, Sweden..
    SEtSim: A modular simulation tool for switched Ethernet networks2016Ingår i: Journal of systems architecture, ISSN 1383-7621, E-ISSN 1873-6165, Vol. 65, s. 1-14Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using high bandwidth network technologies in real-time applications, for example in automotive systems, is rapidly increasing. In this context, switched Ethernet-based protocols are becoming more popular due to their features such as providing a collision-free domain for transmission of messages. Moreover, switched Ethernet is a mature technology. Several protocols based on switched Ethernet have been proposed over the years, tuned for time critical applications. However, research for improving the features and performance of these protocols is still on-going. In order to evaluate the performance of early stage proposed protocols, the mathematical analysis and/or experiments are required. However, performing an experiment for complex network topologies with a large set of messages is not effortless. Therefore, using a simulation based approach for evaluating a protocol's performance and/or properties is highly useful. As a response to this we have developed a simulator, called SEtSim, for switched Ethernet networks. SEtSim is developed based on Simulink, and it currently supports different network topologies of the FIT-SE protocol as well as Ethernet AVB protocol. However, the kernel of SEtSim is designed such that it is possible to add and integrate other switched Ethernet-based protocols. In this paper, we describe the design of SEtSim and we show its scalability.

  • 17.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    SEtSim: A Modular Simulation Tool for Switched Ethernet Networks2014Rapport (Övrigt vetenskapligt)
    Abstract [en]

    Using high bandwidth network technologies in real-time applications, for example in automotive systems, is rapidly increasing. In this context, switched Ethernet-based protocols are becoming more popular due to their features such as providing a collision-free domain for transmission of messages. Moreover, switched Ethernet is a mature technology. Several protocols based on switched Ethernet have been proposed over the years, tuned for time critical applications. However, research for improving the features and performance of these protocols is still on-going. In order to evaluate the performance of early stage proposed protocols, the mathematical analysis and/or experiments are required. However, performing an experiment for complex network topologies with a large set of messages is not effortless. Therefore, using a simulation based approach for evaluating a protocol's performance and/or properties is highly useful. As a response to this we have, based on Simulink, developed a simulator, called SEtSim, for switched Ethernet networks. SEtSim currently supports different network topologies of the FTT-SE protocol, a master-slave protocol designed for standard Ethernet switches, as well as Ethernet AVB protocol. However, the kernel of SEtSim is designed such that it is possible to add and integrate other switched Ethernet-based protocols. In this paper, we describe the design of SEtSim and we show its scalability.

  • 18.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik.
    The Design and Implementation of a Simulator for Switched Ethernet Networks2012Ingår i: 3rd International Workshop on Analysis Tools andMethodologies for Embeddedand Real-time Systems / [ed] Tommaso Cucinotta and Giuseppe Lipari, 2012, s. 57-62Konferensbidrag (Refereegranskat)
    Abstract [en]

    In the context of Switched Ethernet, the Flexible Time-Triggered Switched Ethernet protocol (FTT-SE) was proposed to overcome the limitations and related problems of using COTS switches in real-time networks, such as overflow of switch queues due to uncontrolled arrival of packets. Although the FTT-SE protocol has been validated by several experiments on real applications, evaluation of different architectures as well as evaluation of large scale networks is not straightforward. Therefore, a simulator to evaluate different network architectures based on the FTT-SE protocol is useful. In this paper we present such a simulator. We address the extended FTT-SE protocol using multiple switches and we present a modular simulator based on Simulink/Matlab to visualize message transmissions and to evaluate end-to-end delay bounds of messages.

  • 19.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Almeida, Luis
    University of Porto.
    Marau, Ricardo
    University of Porto.
    A Compact Approach to Clustered Master-Slave Ethernet Networks2012Ingår i: IEEE International Workshop on Factory Communication Systems - Proceedings, WFCS, 2012, s. 157-160Konferensbidrag (Refereegranskat)
    Abstract [en]

    Ethernet switches are increasingly used in real-time distributed systems as a technical solution to guarantee the timeliness in communications. However, there are still limitations related to real-time behavior caused by the limited number of priority levels and the possibility of memory overruns with consequent message losses. These limitations can be eliminated using a master/slave technique such as proposed by the FTT paradigm. This led to the FTT-SE protocol that schedules transmissions centrally in a master node. While this protocol has already been well studied and investigated for small networks with a single switch, its extension to larger networks is still an open issue. In this paper we propose a compact clustered solution to scale the FTT-SE protocol to networks of multiple switches by organizing the network in sub-networks composed of one master and one switch each and which can be connected directly, without bridges. This paper also shows how the timeliness of the traffic can still be enforced. The validation is currently on-going.

  • 20.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Pedreiras, Paulo
    University of Aveiro, Portugal.
    Bril, Reinder J.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Almeida, Luis
    University of Porto, Portugal.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Reduced Buffering Solution for Multi-Hop HaRTES Switched Ethernet Networks2014Ingår i: The 20th IEEE International Conference on embedded and Real-Time Computing Systems and Applications RTCSA'14, 2014, s. Article number 6910504-Konferensbidrag (Refereegranskat)
    Abstract [en]

    In the context of switched Ethernet networks, multi-hop communication is essential as the networks in industrial applications comprise a high amount of nodes, that is far beyond the capability of a single switch. In this paper, we focus on multi-hop communication using HaRTES switches. The HaRTES switch is a modified Ethernet switch that provides real-time traffic scheduling, dynamic Quality-of-Service and temporal isolation between real-time and non-real-time traffic. Herein, we propose a method, called Reduced Buffering Scheme, to conduct the traffic through multiple HaRTES switches in a multi-hop HaRTES architecture. In order to enable the new scheduling method we propose to modify the HaRTES switch structure. Moreover, we develop a response time analysis for the new method. We also compare the proposed method with a method previously proposed, called Distributed Global Scheduling, based on their traffic response times. We show that, the new method forwards all types of traffic including the highest, the medium and the lowest priority, faster than the previous method in most of the cases. Furthermore, we show that the new method performs even better for larger networks compared with the previous one.

  • 21.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Rodriguez-Navas, Guillermo
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Universitat de les Illes Balears, Spain.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Implementing a Clock Synchronization Protocol on a Multi-Master Switched Ethernet Network2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    The interest to use Switched Ethernet technologies in real-time communication is increasing due to its absence of collisions when transmitting messages. Nevertheless, using COTS switches affect the timeliness guarantee inherent in potentially overflowing internal FIFO queues. In this paper we focus on a solution, called the FTT-SE protocol, which is developed based on a master-slave technique. Recently, an extension of the FTT-SE protocol has been proposed where the transmission of messages are controlled using multiple master nodes. In order to guarantee the correctness of the protocol, the masters should be timely synchronized. Therefore, in this paper we investigate using a clock synchronization protocol, based on the IEEE 1588 standard, among master nodes and we study the effects of this protocol on the network performance. In addition, we present a formal verification of this solution by means of model checking to prove the correctness of the FTT-SE protocol when the clock synchronization protocol is applied.

  • 22.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Du, Yong
    Almeida, L.
    University of Porto, Porto, Portugal .
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Dynamic reconfiguration in HaRTES switched ethernet networks2016Ingår i: IEEE International Workshop on Factory Communication Systems - Proceedings, WFCS, 2016, artikel-id Article number 7496510Konferensbidrag (Refereegranskat)
    Abstract [en]

    The ability of reconfiguring a system during runtime is essential for dynamic real-time applications in which resource usage is traded online for quality of service. The HaRTES switch, which is a modified Ethernet switch, holds this ability for the network resource, and at the same time it provides hard real-time support for both periodic and sporadic traffic. Although the HaRTES switch technologically caters this ability, a protocol to actually perform the dynamic reconfiguration is missing in multi-hop HaRTES networks. In this paper we introduce such a protocol that is compatible with the traffic scheduling method used in the architecture. We prove the correctness of the protocol using a model checking technique. Moreover, we conduct a set of simulation experiments to show the performance of the protocol and we also show that the reconfiguration process is terminated within a bounded time. 

  • 23.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Khalilzad, Nima
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. IS (Embedded Systems).
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Sander, Ingo
    Royal Institute of Technology, Sweden.
    Almeida, Luis
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Designing End-to-end Resource Reservations in Predictable Distributed Embedded Systems2017Ingår i: Real-time systems, ISSN 0922-6443, E-ISSN 1573-1383, Vol. 53, nr 6, s. 916-956Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Contemporary distributed embedded systems in many domains have become highly complex due to ever-increasing demand on advanced computer controlled functionality. The resource reservation techniques can be effective in lowering the software complexity, ensuring predictability and allowing flexibility during the development and execution of these systems. This paper proposes a novel end-to-end resource reservation model for distributed embedded systems. In order to support the development of predictable systems using the proposed model, the paper provides a method to design resource reservations and an end-to-end timing analysis. The reservation design can be subjected to different optimization criteria with respect to runtime footprint, overhead or performance. The paper also presents and evaluates a case study to show the usability of the proposed model, reservation design method and end-to-end timing analysis. 

  • 24.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Liu, Meng
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Mifdaoui, A.
    University of Toulouse, France.
    Almeida, L.
    University of Porto, Portugal.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik.
    Worst-case delay analysis of master-slave switched ethernet networks2012Ingår i: Proceeings of the 2nd International Workshop on Worst-Case Traversal Time: Proceeding, 2012, s. 15-21Konferensbidrag (Refereegranskat)
    Abstract [en]

    Switched Ethernet is increasingly used in real-time communication due to its intrinsic features such as micro segmentation and high throughput. However, COTS switches may impose long blocking times due to their FIFO queues and can also experience buffer overflow in outgoing queues due to uncontrolled packets arrival. The FTT-SE protocol uses a Master-Slave technique to overcome the COTS switch limitations in real-time applications. Recently, we extended the protocol for large scale networks and in this paper we present the worst-case delay analysis using the Network Calculus formalism for such a network. Moreover, we assess the end-to-end delay of traffic with simulation concluding that the obtained analytical results present a good match with the observed delays, providing uppers bounds that vary between 0% and 50% above the maximum measured values. © 2012 ACM.

  • 25.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Almeida, Luis
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    End-to-end Resource Reservations in Distributed Embedded Systems2016Ingår i: Proceedings - 2016 IEEE 22nd International Conference on Embedded and Real-Time Computing Systems and Applications, RTCSA 2016, 2016, s. 1-11, artikel-id 7579921Konferensbidrag (Refereegranskat)
    Abstract [en]

    The resource reservation techniques provide effective means to lower the software complexity, ensure predictability and allow flexibility during the development and execution of complex distributed embedded systems. In this paper we propose a new end-to-end resource reservation model for distributed embedded systems. The model is comprehensive in such a way that it supports end-to-end resource reservations on distributed transactions with various activation patterns that are commonly used in industrial control systems. The model allows resource reservations on processors and real-time network protocols. We also present timing analysis for the distributed embedded systems that are developed using the proposed model. The timing analysis computes the end-to-end response times as well as delays such as data age and reaction delays. The presented analysis also supports real-time networks that can autonomously initiate transmissions. Such networks are not supported by the existing analyses. We also include a case study to show the usability of the model and end-to-end timing analysis with resource reservations.

  • 26.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    End-to-end Resource Reservation Model2016Manuskript (preprint) (Övrigt vetenskapligt)
  • 27.
    Ashjaei, Mohammad
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Daneshtalab, Masoud
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Casamayor, Victor
    Technical University of Vienna, Austria.
    Nelissen, Geoffrey
    Eindhoven University of Technology, Netherlands.
    Towards a Predictable and Cognitive Edge-Cloud Architecture for Industrial Systems2022Ingår i: Proceedings of RAGE 2022, 2022Konferensbidrag (Refereegranskat)
  • 28.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Patti, Gaetano
    University of Catania, Italy.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Alderisi, Giuliana
    University of Catania, Italy.
    Lo Bello, Lucia
    University of Catania, Italy.
    Schedulability Analysis of Ethernet Audio Video Bridging Networks with Scheduled Traffic Support2017Ingår i: Real-time systems, ISSN 0922-6443, E-ISSN 1573-1383, Vol. 53, nr 4, s. 526-577Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The IEEE Audio Video Bridging (AVB) technology is nowadays under consideration in several automation domains, such as, automotive, avionics, and industrial communications. AVB offers several benefits, such as open specifications, the existence of multiple providers of electronic components, and the real-time support, as AVB provides bounded latency to real-time traffic classes. In addition to the above mentioned properties, in the automotive domain, comparing with the existing in-vehicle networks, AVB offers significant advantages in terms of high bandwidth, significant reduction of cabling costs, thickness and weight, while meeting the challenging EMC/EMI requirements. Recently, an improvement of the AVB protocol, called the AVB ST, was proposed in the literature, which allows for supporting scheduled traffic, i.e., a class of time-sensitive traffic that requires time-driven transmission and low latency. In this paper, we present a schedulability analysis for the real-time traffic crossing through the AVB ST network. In addition, we formally prove that, if the bandwidth in the network is allocated according to the AVB standard, the schedulability test based on response time analysis will fail for most cases even if, in reality, these cases are schedulable. In order to provide guarantees based on analysis test a bandwidth over-reservation is required. In this paper, we propose a solution to obtain a minimized bandwidth over-reservation. To the best of our knowledge, this is the first attempt to formally spot the limitation and to propose a solution for overcoming it. The proposed analysis is applied to both the AVB standard and the AVB ST. The analysis results are compared with the results of several simulative assessments, obtained using OMNeT++, on both automotive and industrial case studies. The comparison between the results of the analysis and the simulation ones shows the effectiveness of the analysis proposed in this work.

  • 29.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Pedreiras, P.
    University of Aveiro, Aveiro, Portugal .
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Almeida, L.
    University of Porto, Porto, Portugal.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Evaluation of dynamic reconfiguration architecture in multi-hop switched ethernet networks2014Ingår i: 19th IEEE International Conference on Emerging Technologies and Factory Automation, ETFA 2014, 2014, s. Article number 7005322-Konferensbidrag (Refereegranskat)
    Abstract [en]

    On-the-fly adaptability and reconfigurability are recently becoming an interest in real-time communications. To assure a continued real-time behavior, the admission control with a quality-of-service mechanism is required, that screen all adaptation and reconfiguration requests. In the context of switched Ethernet networks, the FTT-SE protocol provides adaptive real-time communication. Recently, we proposed two methods to perform the online reconfiguration in multi-hop FTT-SE architectures. However, the methods lack the experimental evaluation. In this paper, we evaluate both methods in terms of the reconfiguration time. 

  • 30.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Pedreiras, P.
    DETI/IT, University of Aveiro, Aveiro, Portugal .
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Bril, Reinder J.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. Technische Universiteit Eindhoven (TU/e), Netherlands .
    Almeida, L.
    Technische Universiteit Eindhoven (TU/e), Netherlands .
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Response time analysis of multi-hop HaRTES Ethernet Switch networks2014Ingår i: IEEE Int. Workshop Factory Commun. Syst. Proc. WFCS, 2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we focus on micro-segmented switched-Ethernet networks with HaRTES switches. HaRTES switches provide synchronous and asynchronous real-time traffic scheduling, dynamic Quality-of-Service adaptation and transparent integration of real-time and non-real-time nodes. Herein we investigate the challenges of connecting multiple HaRTES switches in order to build multi-hop communication and we propose a method, named Distributed Global Scheduling, to handle the traffic forwarding in such an architecture while preserving the unique properties of the single HaRTES switch case. Moreover, we develop a response time analysis for the method. We also evaluate the level of pessimism embodied in the anal-ysis. Finally, we show the applicability of the proposed method in an industrial setting by applying it in an automotive case study.

  • 31.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Pedreiras, Paulo
    University of Aveiro, Portugal.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Almeida, Luis
    University of Porto, Portugal.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Dynamic Reconfiguration in Multi-Hop Switched Ethernet Networks2014Ingår i: ACM SIGBED Review. Special Issue on 6th Workshop on Adaptive and Reconfigurable Embedded Systems (APRES 2014), ISSN 1551-3688, Vol. 11, nr 3, s. 62-65Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The FTT-SE protocol provides adaptive real-time communication on Ethernet networks. To assure a continued real-time behavior, FTT-SE integrates admission control with a quality-of-service mechanism, which screen all adaptation and reconfiguration requests, accepting only those that do not compromise the system timeliness. The adaptability and reconfigurability have been deeply studied in the case of single switch FTT-SE architectures, whereas the extension of that for the multi-hop FTT-SE architecture was not yet investigated. Therefore, in this paper we study the challenges of enabling dynamic reconfiguration in multi-hop FTT-SE networks, we propose two methods (one centralized and one distributed) and we present a qualitative comparison between them.

  • 32.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Pedreiras, Paulo
    University of Aveiro, Portugal.
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Almeida, Luis
    University of Porto, Portugal.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Supporting Multi-Hop Communications with HaRTES Ethernet Switches2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper we identify the challenges of multi-hop communication when using a micro-segmented switched-Ethernet protocol with enhanced HaRTES switches. The HaRTES architecture has been explored in the scope of single-switch topology, and provides dynamic virtual channels that can be composed hierarchically and provide bounded latency together with temporal isolation. Herein we propose two different solutions regarding the traffic forwarding in multi-switch architectures, while maintaining the unique properties of the single HaRTES switch case. In the first approach, the traffic is buffered and scheduled sequentially in each hop. In the second solution the traffic is scheduled once and forwarded immediately through multiple switches without buffering. In this paper we present a brief comparison of both approaches and we report on the on-going work towards effective support to real-time communications in dynamic and complex Cyber-Physical Systems.

  • 33.
    Ashjaei, Mohammad
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. MRTC Malardalen Univ, Vasteras, Sweden..
    Silva, Luis
    DETI IT Univ Aveiro, Aveiro, Portugal..
    Behnam, Moris
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. MRTC Malardalen Univ, Vasteras, Sweden..
    Pedreiras, Paulo
    DETI IT Univ Aveiro, Aveiro, Portugal..
    Bril, Reinder J.
    Tech Univ Eindhoven TU E, Eindhoven, Netherlands..
    Almeida, Luis
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. MRTC Malardalen Univ, Vasteras, Sweden.;IT DEEC Univ Porto, Oporto, Portugal..
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system. MRTC Malardalen Univ, Vasteras, Sweden..
    Improved Message Forwarding for Multi-Hop HaRTES Real-Time Ethernet Networks2016Ingår i: Journal of Signal Processing Systems, ISSN 1939-8018, E-ISSN 1939-8115, Vol. 84, nr 1, s. 47-67Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Nowadays, switched Ethernet networks are used in complex systems that encompass tens to hundreds of nodes and thousands of signals. Such scenarios require multi-switch architectures where communications frequently occur in multiple hops. In this paper we investigate techniques to allow efficient multi-hop communication using HaRTES switches. These are modified Ethernet switches that provide real-time traffic scheduling, dynamic bandwidth management and temporal isolation between real-time and non-real-time traffic. This paper addresses the problem of forwarding traffic in HaRTES networks. Two methods have been recently proposed, namely Distributed Global Scheduling (DGS) that buffers traffic between switches, and Reduced Buffering Scheme (RBS), that uses immediate forwarding. In this paper, we discuss the design and implementation of RBS within HaRTES and we carry out an experimental validation with a prototype implementation. Then, we carry out a comparison between RBS and DGS using worst-case response time analysis and simulation. The comparison clearly establishes the superiority of RBS concerning end-to-end response times. In fact, with sample message sets, we achieved reductions in end-to-end delay that were as high as 80 %.

  • 34.
    Ashjaei, Seyed Mohammad Hossein
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Becker, Matthias
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Cloud Computing in Factory Automation: A Survey and Open Problems2020Rapport (Övrigt vetenskapligt)
  • 35.
    Ashjaei, Seyed Mohammad Hossein
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Bengtsson, Marcus
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering. IS (Embedded Systems).
    Enhancing Smart Maintenance Management Using Fog Computing Technology2017Ingår i: 2017 International Conference on Industrial Engineering and Engineering Management IEEM, 2017, s. 1561-1565Konferensbidrag (Refereegranskat)
    Abstract [en]

    In order for factories to stay competitive in the current open global market, there should be efforts to put on optimizing the value stream of producing goods. Within this context, Industrial Internet of Things (IIoT) has been emerged as a technology aiming at achieving high productivity performance in manufacturing. A smart manufacturing approach also requires a smart maintenance management as it plays a crucial role in securing the productivity. IIoT applications are traditionally completed by the cloud computing technology to serve the required services. In this paper, we argue that maintenance processes have requirements that cannot be accomplished by solely the cloud computing technology. We identify several of these requirements. Then, we propose a platform using the fog computing technology, as a recently raised technology in IIoT, to enhance the smart maintenance management. We also discuss the ability of the platform in fulfilling the identified requirements.

  • 36.
    Ashjaei, Seyed Mohammad Hossein
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Bucaioni, Alessio
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    A Conceptual Framework for Software Modeling of Automation Systems2022Ingår i: ITNG 2022 19th International Conference on Information Technology-New Generations. Advances in Intelligent Systems and Computing, vol 1421, 2022, Vol. 1421Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we propose a conceptual framework to facilitate the design and development of an automation system in which time-sensitive networking (TSN) is utilized for the backbone network and OPC UA is used for modeling of data exchange over TSN. As the configuration of OPC UA over TSN in a large automation setup can be a challenging task and requires specific expertise, we propose to add an abstract modeling layer that adopts the concepts of model-based development and component-based software engineering to facilitate the development of these systems. The proposed conceptual model can be automatically translated to the OPC UA modeling format. Such a modeling view will significantly reduce the complexity of OPC UA configurations, specially in large automation systems. Another benefit of the proposed framework is that the engineers, who do not have high levels of expertise in OPC UA, will be able to easily configure the OPC UA nodes in the automation system that utilize TSN for backbone communication.

  • 37.
    Ashjaei, Seyed Mohammad Hossein
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Clegg, Kester
    Univ York, York, N Yorkshire, England..
    Corneo, Lorenzo
    Uppsala Univ, Uppsala, Sweden..
    Hawkins, Richard
    Univ York, York, N Yorkshire, England..
    Jaradat, Omar
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Gulisano, Vincenzo Massimiliano
    Chalmers Univ, Gothenburg, Sweden..
    Nikolakopoulos, Yiannis
    Chalmers Univ, Gothenburg, Sweden..
    Service Level Agreements for Safe and Configurable Production Environments2018Ingår i: 2018 IEEE 23RD INTERNATIONAL CONFERENCE ON EMERGING TECHNOLOGIES AND FACTORY AUTOMATION (ETFA), IEEE , 2018, s. 1252-1255Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper focuses on Service Level Agreements (SLAs) for industrial applications that aim to port some of the control functionalities to the cloud. In such applications, industrial requirements should be reflected in SLAs. In this paper, we present an approach to integrate safety-related aspects of an industrial application to SLAs. We also present the approach in a use case. This is an initial attempt to enrich SLAs for industrial settings to consider safety aspects, which has not been investigated thoroughly before.

  • 38.
    Ashjaei, Seyed Mohammad Hossein
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Girs, Svetlana
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Dynamic Resource Distribution using SDN in Wireless Networks2020Ingår i: 21st IEEE International Conference on Industrial Technology ICIT'20, 2020, s. 967-972Konferensbidrag (Refereegranskat)
  • 39.
    Ashjaei, Seyed Mohammad Hossein
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Khalilzad, Nima
    Qamcom Research and Technology, Stockholm, Sweden.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Modeling, Designing and Analyzing Resource Reservations in Distributed Embedded Systems2018Ingår i: Real-Time Modelling and Processing for Communication Systems / [ed] Springer, Springer , 2018, s. 203-256Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 40.
    Ashjaei, Seyed Mohammad Hossein
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Lo Bello, L.
    University of Catania, Italy.
    Daneshtalab, Masoud
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Patti, G.
    University of Catania, Italy.
    Saponara, S.
    University of Pisa, Italy.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Time-Sensitive Networking in automotive embedded systems: State of the art and research opportunities2021Ingår i: Journal of systems architecture, ISSN 1383-7621, E-ISSN 1873-6165, Vol. 117, artikel-id 102137Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The functionality advancements and novel customer features that are currently found in modern automotive systems require high-bandwidth and low-latency in-vehicle communications, which become even more compelling for autonomous vehicles. In a recent effort to meet these requirements, the IEEE Time-Sensitive Networking (TSN) task group has developed a set of standards that introduce novel features in Switched Ethernet. TSN standards offer, for example, a common notion of time through accurate and reliable clock synchronization, delay bounds for real-time traffic, time-driven transmissions, improved reliability, and much more. In order to fully utilize the potential of these novel protocols in the automotive domain, TSN should be seamlessly integrated into the state-of-the-art and state-of-practice model-based development processes for automotive embedded systems. Some of the core phases in these processes include software architecture modeling, timing predictability verification, simulation, and hardware realization and deployment. Moreover, throughout the development of automotive embedded systems, the safety and security requirements specified on these systems need to be duly taken into account. In this context, this work provides an overview of TSN in automotive applications and discusses the recent technological developments relevant to the adoption of TSN in automotive embedded systems. The work also points at the open challenges and future research directions. 

  • 41.
    Ashjaei, Seyed Mohammad Hossein
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Lundbäck, John
    Arcticus Systems AB, Sweden.
    Gålnander, Mattias
    Arcticus Systems AB, Sweden.
    Lundbäck, Kurt-Lennart
    Arcticus Systems AB, Sweden.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Modeling and Timing Analysis of Vehicle Functions Distributed over Switched Ethernet2017Ingår i: IECON 2017 - 43RD ANNUAL CONFERENCE OF THE IEEE INDUSTRIAL ELECTRONICS SOCIETY, 2017, s. 8419-8424Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper proposes an approach to model switched Ethernet communication within a model- and component-based software development framework for vehicular distributed embedded systems. The paper also presents a method to extract the network timing model from the systems that use switched Ethernet networks. In order to provide a proof of concept, an existing industrial component model and its tool suite, namely RCM and Rubus-ICE respectively, are extended by implementing the modeling technique, the timing model extraction method and response-time analysis of the Ethernet AVB protocol. The extensions to RCM are backward compatible with the modeling and end-to-end timing analysis of traditional in-vehicle networks and legacy (previously developed) vehicular distributed embedded systems. Furthermore, the paper discusses the implementation and test strategy used in this work. Finally, the usability of the modeling approach and implemented timing analysis is demonstrated by modeling and time analyzing a vehicular application case study with the extended component model and tool suite.

  • 42.
    Ashjaei, Seyed Mohammad Hossein
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Murselović, Lejla
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Implications of Various Preemption Configurations in TSN Networks2022Ingår i: IEEE Embedded Systems Letters, ISSN 1943-0663, Vol. 14, nr 1, s. 39-42Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Time Sensitive Networking (TSN) is a set of standards developed by the IEEE 802.1 task group to support high-bandwidth and low latency predictable network communication. Configuration of TSN networks is a daunting task as there are several novel features in TSN and numerous possibilities can arise by considering combinations of these features. This letter investigates the impact of various unexplored frame-preemption configurations in TSN networks on the timing behaviours of various traffic classes. These configurations correspond to different combinations of settings in TSN with respect to the credit-based shaper, time-aware shaper, Hold & Release mechanism and frame preemption. The letter provides evaluation of these configurations by means of an analytical discussion and simulation experiments. The results and implications discussed in this letter can serve as useful guidelines for the network designers when configuring TSN networks with regards to the addressed features.

  • 43.
    Ashjaei, Seyed Mohammad Hossein
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Sjödin, Mikael
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    A novel frame preemption model in TSN networks2021Ingår i: Journal of systems architecture, ISSN 1383-7621, E-ISSN 1873-6165, Vol. 116, artikel-id 102037Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper identifies a limitation in the frame preemption model in the TSN standard (IEEE 802.1Q-2018), due to which high priority frames can experience significantly long blocking delays, thereby exacerbating their worst-case response times. This limitation can have a considerable impact on the design, analysis and performance of TSN-based systems. To address this limitation, the paper presents a novel and more efficient frame preemption model in the TSN standard that allows over 90% reduction in the maximum blocking delay leading to lower worst-case response times of high priority frames compared to the frame preemption model used in the existing works. The paper also shows that the improvement becomes even more significant in multi-switch TSN networks. In order to evaluate the effects of preemption, the paper performs simulations by enabling and disabling preemptions as well as enabling and disabling the Hold/Release mechanism supported by TSN. Furthermore, the paper performs a comparative evaluation of the two models of frame preemption in TSN using simulations. The evaluation shows that the maximum response times of high priority frames can be significantly reduced with very small impact on the response times of lower priority frames. The paper also shows the improvement in the maximum response times of higher priority frames using an automotive industrial use case that employs a multi-hop TSN network for on-board communication.

  • 44.
    Berisa, Aldin
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Daneshtalab, Masoud
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Sjödin, Mikael
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Investigating and Analyzing CAN-to-TSN Gateway Forwarding Techniques2023Ingår i: Proc. - IEEE Int. Symp. Real-Time Distrib. Comput., ISORC, Institute of Electrical and Electronics Engineers Inc. , 2023, s. 136-145Konferensbidrag (Refereegranskat)
    Abstract [en]

    Controller Area Network (CAN) and Ethernet network are expected to co-exist in automotive industry as Ethernet provides a high-bandwidth communication, while CAN is a legacy cost-effective solution. Due to the shortcomings of conventional switched Etherent, such as determinism, IEEE Time Sensitive Networking (TSN) task group developed a set of standards to enhance the switched Ethernet technology providing low-jitter and deterministic communication. Considering these two network domains, we investigate various design approaches for a gateway that connects a CAN domain to a TSN domain. We present three gateway forwarding techniques and we develop end-to-end delay analysis methods for them. Via the analysis methods and applying them to synthetic use cases we show that the intuitive existing approach of encapsulating multiple CAN frames into a single Ethernet frame is not necessarily an efficient solution. In fact, we demonstrate several cases where it is preferable to encapsulate only one CAN frame into a TSN frame, in particular when we use a high speed TSN network. The results have a significant impact on developing such gateways as the implementation of the one-to-one frame encapsulation is considerably simpler than other complex gateway-forwarding techniques.

  • 45.
    Berisa, Aldin
    et al.
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Panjevic, A.
    Arcticus Systems, Järfälla, Sweden.
    Kovac, I.
    Arcticus Systems, Järfälla, Sweden.
    Lyngbäck, H.
    HIAB, Hudiksvall, Sweden.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Daneshtalab, Masoud
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Sjödin, Mikael
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Comparative Evaluation of Various Generations of Controller Area Network Based on Timing Analysis2023Ingår i: IEEE Int. Conf. Emerging Technol. Factory Autom., ETFA, Institute of Electrical and Electronics Engineers Inc. , 2023Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper performs a comparative evaluation of various generations of Controller Area Network (CAN), including the classical CAN, CAN Flexible Data-Rate (FD), and CAN Extra Long (XL). We utilize response-time analysis for the evaluation. In this regard, we identify that the state of the art lacks the response-time analysis for CAN XL. Hence, we discuss the worst-case transmission times calculations for CAN XL frames and incorporate them to the existing analysis for CAN to support response-time analysis of CAN XL frames. Using the extended analysis, we perform a comparative evaluation of the three generations of CAN by analyzing an automotive industrial use case. In crux, we show that using CAN FD is more advantageous than the classical CAN and CAN XL when using frames with payloads of up to 8 bytes, despite the fact that CAN XL supports higher bit rates. For frames with 12-64 bytes payloads, CAN FD performs better than CAN XL when running at the same bit rate, but CAN XL performs better when running at a higher bit rate. Additionally, we discovered that CAN XL performs better than the classical CAN and CAN FD when the frame payload is over 64 bytes, even if it runs at the same or higher bit rates than CAN FD.

  • 46.
    Berisa, Aldin
    et al.
    Mälardalens universitet.
    Zhao, L.
    Beihang University, Beijing, China.
    Craciunas, S. S.
    TTTech Computertechnik Ag, Vienna, Austria.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Daneshtalab, Masoud
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Sjödin, Mikael
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    AVB-aware Routing and Scheduling for Critical Traffic in Time-sensitive Networks with Preemption2022Ingår i: ACM International Conference Proceeding Series, Association for Computing Machinery , 2022, s. 207-218Konferensbidrag (Refereegranskat)
    Abstract [en]

    The Time-Sensitive Network (TSN) amendments and protocols add capabilities on top of standard 802.1 Ethernet for guaranteeing the timeliness of both (isochronous) scheduled traffic (ST) and shaped (audio-video) communication (AVB) in distributed applications. ST streams are guaranteed via an offline computed schedule controlling the time-aware gate mechanism of IEEE 802.1Qbv, while AVB real-time streams are shaped via a credit-based shaper (CBS) and scheduler with lower-priority than ST. Although the two traffic classes use different TSN mechanisms, they are interrelated as the ST traffic class schedule influences the latency of AVB traffic. In this paper, we propose a method for the integration of the ST schedule synthesis with an analysis for the AVB class featuring IEEE 802.1Qbu frame preemption under different configurations to reduce the interference between the two classes. We first present a new worst-case response-time (WCRT) analysis for the AVB traffic class in TSN networks with preemption, considering an arbitrary number of AVB queues and different configurations for the CBS credit behavior. Then, we integrate the creation of ST schedule tables with the schedulability analysis of AVB traffic using a heuristic algorithm featuring frame preemption and a novel routing mechanism aimed at maximizing AVB schedulability. Finally, we evaluate our approach using both real-world and synthetic use cases showing the efficiency both in terms of schedule creation runtime and in terms of increasing the schedulability of lower-priority AVB traffic.

  • 47.
    Bucaioni, Alessio
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Lundbäck, John
    Arcticus Systems AB, Sweden.
    Gålnander, Mattias
    Arcticus Systems AB, Sweden.
    Lundbäck, Kurt-Lennart
    Arcticus Systems AB, Sweden.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Becker, Matthias
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Mubeen, Saad
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Modelling and Timing Analysis of Real-time Applications on Evolving Automotive E/E Architectures using Rubus-ICE2019Ingår i: Open Demo Session of Real-Time Systems 2019 RTSS@Work'19, Hong Kong, HongKong, 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    The automotive E/E architectures are evolving from the traditional distributed architectures to upcoming consolidated domain architectures and possibly future centralised architectures. This paper demonstrates modelling and timing analysis of real-time embedded systems on contemporary automotive E/E architectures using the Rubus-ICE tool suite. The Rubus concept and tool suite, developed and evolved based on close academic-industrial collaboration, have been used in the automotive industry for over 25 years. The paper also demonstrates recent extensions and discusses proposals to support the modelling and timing analysis of the systems on future E/E architectures.

  • 48.
    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.
    Papadopoulos, Alessandro
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Nolte, Thomas
    Mälardalens universitet, Akademin för innovation, design och teknik, Inbyggda system.
    Proenza, J.
    University of the Balearic Islands, Spain.
    HERMES: Heuristic Multi-queue Scheduler for TSN Time-Triggered Traffic with Zero Reception Jitter Capabilities2022Ingår i: ACM International Conference Proceeding Series, Association for Computing Machinery , 2022, s. 70-80Konferensbidrag (Refereegranskat)
    Abstract [en]

    The Time-Sensitive Networking (TSN) standards provide a toolbox of features to be utilized in various application domains.The core TSN features include deterministic zero-jitter and low-latency data transmission and transmitting traffic with various levels of time-criticality on the same network. To achieve a deterministic transmission, the TSN standards define a time-aware shaper that coordinates transmission of Time-Triggered (TT) traffic. In this paper, we tackle the challenge of scheduling the TT traffic and we propose a heuristic algorithm, called HERMES. Unlike the existing scheduling solutions, HERMES results in a significantly faster algorithm run-time and a high number of schedulable networks. HERMES can be configured in two modes of zero or relaxed reception jitter while using multiple TT queues to improve the schedulability. We compare HERMES with a constraint programming (CP)-based solution and we show that HERMES performs better than the CP-based solution if multiple TT queues are used, both with respect to algorithm run-time and schedulability of the networks.

  • 49.
    Bujosa Mateu, Daniel
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Ashjaei, Seyed Mohammad Hossein
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Papadopoulos, Alessandro
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Proenza, Julián
    Universitat de les Illes Balears, Spain.
    Nolte, Thomas
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    LETRA: Mapping Legacy Ethernet-Based Traffic into TSN Traffic Classes2021Ingår i: 26th IEEE International Conference on Emerging Technologies and Factory Automation ETFA 2021, Västerås, Sweden: IEEE, 2021Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper proposes a method to efficiently map the legacy Ethernet-based traffic into Time Sensitive Networking (TSN) traffic classes considering different traffic characteristics. Traffic mapping is one of the essential steps for industries to gradually move towards TSN, which in turn significantly mitigates the management complexity of industrial communication systems. In this paper, we first identify the legacy Ethernet traffic characteristics and properties. Based on the legacy traffic characteristics we presented a mapping methodology to map them into different TSN traffic classes. We implemented the mapping method as a tool, named Legacy Ethernet-based Traffic Mapping Tool or LETRA, together with a TSN traffic scheduling and performed a set of evaluations on different synthetic networks. The results show that the proposed mapping method obtains up to 90% improvement in the schedulability ratio of the traffic compared to an intuitive mapping method on a multi-switch network architecture.

  • 50.
    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.

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