Change search
Refine search result
12 1 - 50 of 83
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1.
    Alizadeh, Morteza
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A Survey of Secure Internet of Things in Relation to Blockchain2020In: Journal of Internet Services and Information Security (JISIS), ISSN 2182-2069, E-ISSN 2182-2077, Vol. 10, no 3, p. 47-75Article in journal (Refereed)
    Abstract [en]

    Distributed ledgers and blockchain technologies can improve system security and trustworthiness by providing immutable replicated histories of data. Blockchain is a linked list of blocks containing digitally signed transactions, a cryptographic hash of the previous block, and a timestamp stored in a decentralized and distributed network. The Internet of Things (IoT) is one of the application domains in which security based on blockchain is discussed. In this article, we review the structure and architectures of distributed IoT systems and explain the motivations, challenges, and needs of blockchain to secure such systems. However, there are substantial threats and attacks to blockchain that must be understood, as well as suitable approaches to mitigate them. We, therefore, survey the most common attacks to blockchain systems and the solutions to mitigate them, with the objective of assessing how malicious these attacks are in the IoT context.

    Download full text (pdf)
    fulltext
  • 2.
    Alizadeh, Morteza
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Comparative Analysis of Decentralized Identity Approaches2022In: IEEE Access, E-ISSN 2169-3536, Vol. 10, p. 92273-92283Article in journal (Refereed)
    Abstract [en]

    Decentralization is essential when trust and performance must not depend on a single organization. Distributed Ledger Technologies (DLTs) and Decentralized Hash Tables (DHTs) are examples where the DLT is useful for transactional events, and the DHT is useful for large-scale data storage. The combination of these two technologies can meet many challenges. The blockchain is a DLT with immutable history protected by cryptographic signatures in data blocks. Identification is an essential issue traditionally provided by centralized trust anchors. Self-sovereign identities (SSIs) are proposed decentralized models where users can control and manage their identities with the help of DHT. However, slowness is a challenge among decentralized identification systems because of many connections and requests among participants. In this article, we focus on decentralized identification by DLT and DHT, where users can control their information and store biometrics. We survey some existing alternatives and address the performance challenge by comparing different decentralized identification technologies based on execution time and throughput. We show that the DHT and machine learning model (BioIPFS) performs better than other solutions such as uPort, ShoCard, and BBID.

    Download full text (pdf)
    fulltext
  • 3.
    Alizadeh, Morteza
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    DHT- and Blockchain-based Smart Identification for Video Conferencing2022In: Blockchain: Research and Applications, ISSN 2096-7209, Vol. 3, no 2, article id 100066Article in journal (Refereed)
    Abstract [en]

    Video conferencing applications help people communicate via the Internet and provide a significant and consistent basis for virtual meetings. However, integrity, security, identification, and authentication problems are still universal. Current video conference technologies typically rely on cloud systems to provide a stable and secure basis for executing tasks and processes. At the same time, video conferencing applications are being migrated from centralized to decentralized solutions for better performance without the need for third-party interactions. This article demonstrates a decentralized smart identification scheme for video conferencing applications based on biometric technology, machine learning, and a decentralized hash table combined with blockchain technology. We store users' information on a distributed hash table and transactional events on the distributed ledger after identifying users by implementing machine learning functions. Furthermore, we leverage distributed ledger technology's immutability and traceability properties and distributed hash table unlimited storage feature to improve the system's storage capacity and immutability by evaluating three possible architectures. The experimental results show that an architecture based on blockchain and distributed hash table has better efficiency but needs a longer time to execute than the two other architectures using a centralized database.

  • 4.
    Alizadeh, Morteza
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Efficient Decentralized Data Storage Based on Public Blockchain and IPFS2020In: 2020 IEEE Asia-Pacific Conference on Computer Science and Data Engineering (CSDE), IEEE, 2020Conference paper (Refereed)
    Abstract [en]

    Blockchain technology has enabled the keeping of a decentralized, tamper-proof, immutable, and ordered ledger of transactional events. Efforts to leverage such a ledger may be challenging when data storage requirements exceed most blockchain protocols’ current capacities. Storing large amounts of decentralized data while maintaining system efficiency is the challenge that we target. This paper proposes using the IPFS distributed hash table (DHT) technology to store information immutably and in a decentralized manner to mitigate the high cost of storage. A storage system involving blockchain and other storage systems in concert should be based on immutable data and allow removal of data from malicious users in the DHT. Efficiency is improved by decreasing the overall processing time in the blockchain with the help of DHT technology and introducing an agreement service that communicate with the blockchain via a RESTful API. We demonstrate the applicability of the proposed method and conclude that the combination of IPFS and blockchain provides efficient cryptographic storage, immutable history and overall better efficiency in a decentralized manner.

    Download full text (pdf)
    fulltext
  • 5.
    Alizadeh, Morteza
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Performance Analysis of Verifiable Data Registry Solutions for Decentralized Identifiers2022In: 2022 IEEE Asia-Pacific Conference on Computer Science and Data Engineering (CSDE), IEEE, 2022Conference paper (Refereed)
    Abstract [en]

    User identification in decentralized systems is a demanding task. Identification systems should work resiliently and have efficient performance. Moreover, identification systems should protect the data that they must store against hackers and saboteurs. Keeping a system with decentralized identification without any intervention in the middle has attracted attention to improve earlier centralized identification systems. Decentralized Identifiers (DIDs) constitute a solution for identification divided into different modules. The verifiable data registry is one of the main parts of this technology, which is distributed storage of identity properties. We analyze the decentralized identification data registry and compare the performance of verifiable data registry based on blockchain and the Distributed Hash Table (DHT) on different scales of systems. Our evaluation results show that DHT has better performance. Furthermore, a model based on DHT shows that in addition to immutable storage and faster query time, it makes systems handle or search in data storage with lower searching time compared to Ethereum Blockchain as another immutable secure technology. Finally, our results show that DHT is a better solution than other models in different scenarios. Although blockchain has promising results on a small scale, it still has problems with storage and query time in large-scale systems.

    Download full text (pdf)
    fulltext
  • 6.
    Altmann, Peter
    et al.
    Department of Industrial Systems, RISE Research Institutes of Sweden AB, SE-16440 Kista, Sweden.
    Abbasi, Abdul Ghafoor
    Department of Industrial Systems, RISE Research Institutes of Sweden AB, SE-16440 Kista, Sweden.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Alizadeh, Morteza
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Creating a Traceable Product Story in Manufacturing Supply Chains Using IPFS2020In: 2020 IEEE 19th International Symposium on Network Computing and Applications (NCA) / [ed] Aris Gkoulalas-Divanis, Mirco Marchetti, Dimiter R. Avresky, Boston/New York: IEEE, 2020, p. 11-18Conference paper (Refereed)
    Abstract [en]

    Evolving traceability requirements increasingly challenge manufacturing supply chain actors to collect tamperproof and auditable evidence about what inputs they process, in what way these inputs are used, and what the resulting process outputs are. Traceability solutions based on blockchain technology have shown ways to satisfy the requirements of creating a tamper-proof and auditable trail of traceability data. However, the existing solutions struggle to meet the increasing storage requirements necessary to create an evidence trail using manufacturing data. In this paper, we show a way to create a tamper-proof and auditable evolving product story that uses a decentralized file system called the InterPlanetary File System (IPFS). We also show how using linked data can help auditors derive a traceable product story from such an accumulating evidence trail. The solution proposed herein can supplement existing blockchain-based traceability solutions and enable traceability in global manufacturing supply chains where forming a consortium incurs prohibitive costs and where storage requirements are high.

    Download full text (pdf)
    fulltext
  • 7.
    Aziz, Abdullah
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Chouhan, Shailesh Singh
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Distributed Digital Twins as Proxies-Unlocking Composability & Flexibility for Purpose-Oriented Digital Twins2023In: IEEE Access, E-ISSN 2169-3536, Vol. 11, p. 137577-137593Article in journal (Refereed)
    Abstract [en]

    In the realm of Industrial Internet of Things (IoT) and Industrial Cyber-Physical Systems (ICPS), Digital Twins (DTs) have revolutionized the management of physical entities. However, existing implementations often face constraints due to hardware-centric approaches and limited flexibility. This article introduces a transformative paradigm that harnesses the potential of distributed Digital Twins as proxies, enabling software-centricity and unlocking composability and flexibility for purpose-oriented digital twin development and deployment. The proposed microservices-based architecture, rooted in service-oriented architecture (SOA) and microservices principles, emphasizes reusability, modularity, and scalability. Leveraging the Lean Digital Twin Methodology and packaged business capabilities expedites digital twin creation and deployment, facilitating dynamic responses to evolving industrial demands. This architecture segments the industrial realm into physical and virtual spaces, where core components are responsible for digital twin management, deployment, and secure interactions. By abstracting and virtualizing physical entities into individual digital twins, this approach establishes the groundwork for purpose-oriented composite digital twin creation. Our key contributions involve a comprehensive exposition of the architecture, a practical proof-of-concept (PoC) implementation, and the application of the architecture in a use-case scenario. Additionally, we provide an analysis, including a quantitative evaluation of the proxy aspect and a qualitative comparison with traditional approaches. This assessment emphasizes key properties such as reusability, modularity, abstraction, discoverability, and security, transcending the limitations of contemporary industrial systems and enabling agile, adaptable digital proxies to meet modern industrial demands.

    Download full text (pdf)
    fulltext
  • 8.
    Aziz, Abdullah
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelen, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Romer, Lukas
    Bosch.IO GmbH, Berlin, Germany.
    Jeroschewski, Sven Erik
    Bosch.IO GmbH, Berlin, Germany.
    Kristan, Johannes
    Bosch.IO GmbH, Berlin, Germany.
    Empowering The Eclipse Arrowhead Framework with a Digital Twin as a Proxy Service2022In: 2022 22nd International Conference on Control, Automation and Systems (ICCAS), IEEE , 2022, p. 1716-1721Conference paper (Refereed)
    Abstract [en]

    Eclipse Arrowhead is an open-source framework for industrial automation based on service-oriented principles. It allows the creation of a highly flexible System of Systems (SoS) by defining local clouds for connecting application systems running on industrial cyber-physical systems (ICPSs). However, in an ICPS context, resource constraints and battery-powered devices are facing issues such as high energy consumption, poor service availability, and low-security capabilities. The concept of Digital Twins (DTs) as a proxy (DTaaP) has been defined to address these CPS challenges by providing valuable properties such as energy efficiency, availability, and security. In this paper, we propose a solution to empower the Eclipse Arrowhead Framework (EAF) with DTaaP. Specifically, the proposed solution introduces AHDitto, an Arrowhead-compliant supporting core system, enabling EAF to achieve three DTaaP properties by integrating Eclipse Ditto with EAF.

  • 9.
    Aziz, Abdullah
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    A Study on Industrial IoT for the Mining Industry: Synthesized Architecture and Open Research Directions2020In: IoT, ISSN 2624-831X, Vol. 1, no 2Article, review/survey (Refereed)
    Abstract [en]

    The Industrial Internet of Things (IIoT) has the potential to improve the production and business processes by enabling the extraction of valuable information from industrial processes. The mining industry, however, is rather traditional and somewhat slow to change due to infrastructural limitations in communication, data management, storage, and exchange of information. Most research efforts so far on applying IIoT in the mining industry focus on specific concerns such as ventilation monitoring, accident analysis, fleet and personnel management, tailing dam monitoring, and pre-alarm system while an overall IIoT architecture suitable for the general conditions in the mining industry is still missing. This article analyzes the current state of Information Technology in the mining sector and identifies a major challenge of vertical fragmentation due to the technological variety of various systems and devices offered by different vendors, preventing interoperability, data distribution, and the exchange of information securely between devices and systems. Based on guidelines and practices from the major IIoT standards, a high-level IIoT architecture suitable for the mining industry is then synthesized and presented, addressing the identified challenges and enabling smart mines by automation, interoperable systems, data distribution, and real-time visibility of the mining status. Remote controlling, data processing, and interoperability techniques of the architecture evolve all stages of mining from prospecting to reclamation. The adoption of such IIoT architecture in the mining industry offers safer mine site for workers, predictable mining operations, interoperable environment for both traditional and modern systems and devices, automation to reduce human intervention, and enables underground surveillance by converging operational technology (OT) and information technology (IT). Significant open research challenges and directions are also studied and identified in this paper, such as mobility management, scalability, virtualization at the IIoT edge, and digital twins.

    Download full text (pdf)
    fulltext
  • 10.
    Aziz, Abdullah
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Data Integration Models for Heterogeneous Industrial Systems: A Conceptual Analysis2021In: 2021 26th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA ), IEEE, 2021, p. 1-8Conference paper (Refereed)
    Abstract [en]

    In the industrial automation domain, data integration between heterogeneous systems and architectures is a challenge. Companies and factories are impatient with the selection of technical solutions that are beneficial to local requirements, therefore facing problems of data integration and incompatibility between other systems. There is a need to bridge heterogeneous industrial systems to provide data integration. This article aims to provide guidelines to industrial managers and solution designers to achieve data integration between heterogeneous industrial systems according to their requirements. For this purpose, we have explored the implementation of two data integration models that can be selected based on the state and needs of industrial systems. The first data integration model is based on event-driven architecture (EDA), where Message Queuing Telemetry Transport (MQTT) is deployed as an event broker. The second model is based on the Arrowhead Framework, which is designed by using service-oriented architecture (SOA) principles, where EventHandler provides SOA-based event-driven communication. We conceptually compare and analyze them based on selected criteria essential in an industrial environment. The qualitative analysis of these models is based on proof-of-concept implementations made available for our evaluation.

  • 11.
    Aziz, Abdullah
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Digital Twin as a Proxy for Industrial Cyber-Physical Systems2023In: icWCSN '23: Proceedings of the 2023 10th International Conference on Wireless Communication and Sensor Networks, Association for Computing Machinery (ACM), 2023, p. 85-92Conference paper (Refereed)
    Abstract [en]

    Digital Twin (DT) in industrial cyber-physical systems (ICPS) is an essential concept for Industry 4.0. In recent years, DT architectures and frameworks for the industry have been the focus of several research initiatives regarding analytics, predictive maintenance, virtual evaluation & verification, and fault detection & diagnosis. However, the resource constraint and battery-driven devices in an ICPS environment are facing challenges such as a short life span due to high energy consumption, lower availability of the services, and low-security capabilities. This paper presents a concept of Digital Twin (DT) to be used as a proxy service for constraint devices in ICPS. We present a four-layer architectural model for the DT as a Proxy (DTaaP) that provides valuable properties for resource constraint devices such as energy efficiency, high availability & state persistence, remote & contention controlling, and security. We present a generic proof of concept (PoC) DTaaP implementation by using Eclipse Ditto which is an open-source Digital Twin Framework. We evaluate our artifact against the listed properties through an experimental scenario. We show that DTaaP improves energy efficiency, that the DT can serve as an anchor point for security, and that it provides availability and persistence for duty-cycling devices. We also identify some limitations of Eclipse Ditto for the PoC DTaaP implementation which can be a focus for future research.

    Download full text (pdf)
    fulltext
  • 12.
    Bezerra, Nibia Souza
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Wang, Min
    Network Architecture and Protocols Research, Ericsson .
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Nordberg, Mats
    Network Architecture and Protocols Research, Ericsson .
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    RACH performance in massive machine-type communications access scenario2018Conference paper (Refereed)
    Abstract [en]

    With the increasing number of devices performing Machine-Type Communications (MTC), mobile networks are expected to encounter a high load of burst transmissions. One bottleneck in such cases is the Random Access Channel (RACH) procedure, which is responsible for the attachment of devices, among other things. In this paper, we performed a rich-parameter based simulation on RACH to identify the procedure bottlenecks. A finding from the studied scenarios is that the Physical Downlink Control Channel (PDCCH) capacity for the grant allocation is the main limitation for the RACH capacity rather than the number of Physical Random Access Channel (PRACH) preambles. Guided by our simulation results, we proposed improvements to the RACH procedure and to PDCCH.

  • 13.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Dhanrajani, Siddhant
    Karlsruhe Institute of Technology (KIT), wbk Institute of Production Science, Kaiserstr. 12, 76131 Karlsruhe, Germany.
    Abdalla, Abdelrahman H.
    Politecnico di Milano, Department of Mechanical Engineering, Via la Masa 1, 20156, Milan, Italy.
    Diani, Marco
    Politecnico di Milano, Department of Mechanical Engineering, Via la Masa 1, 20156, Milan, Italy.
    Klenk, Felix
    Karlsruhe Institute of Technology (KIT), wbk Institute of Production Science, Kaiserstr. 12, 76131 Karlsruhe, Germany.
    Colledani, Marcello
    Politecnico di Milano, Department of Mechanical Engineering, Via la Masa 1, 20156, Milan, Italy.
    Palm, Emanuel
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Demand-supply matching through auctioning for the circular economy2021In: 10th CIRP Sponsored Conference on Digital Enterprise Technologies (DET 2020) – Digital Technologies as Enablers of Industrial Competitiveness and Sustainability / [ed] Jozsef Vancza; Paul Maropoulos, Elsevier, 2021, p. 82-87Conference paper (Refereed)
    Abstract [en]

    The circular economy aims to reduce the consumption of resources and energy by exploiting multiple use-cycles of components and materials. The creation of new circular businesses hinges on efficient alignment between market demands of circular products with the supply of End-of-life components and materials. In this paper, we address the digitization of a matchmaking tool for the circular economy by defining demand-supply matching (DSM) in context of business link identification and cross-sectorial matchmaking. We further specify a DSM process and p resent our DSM tool, which facilitates publication and search for supplier offerings and demander needs, selection of auctioning candidates, and digitized auctioning and contract definition. By that, this tool supports the alignment of market demands with matching supply offerings. In particular, it combines the steps of publishing, searching, selecting, auctioning and contract definition into one tool, which we argue can make matchmaking more efficient compared to addressing these steps separately. Finally, we present the design of the tool and discuss its merits in light of the needed acceptance for automating business link identification and contractual interactions.

  • 14.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Jonsson, Andreas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Signals and Systems.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    On creating proportional loss-rate differentiation: predictability and performance2001In: Quality of Service - IWQoS 2001: 9th International Workshop Karlsruhe, Germany, June 6-8, 2001 Proceedings / [ed] Lars Wolf, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2001, p. 372-386Conference paper (Refereed)
    Abstract [en]

    Recent extensions to the Internet architecture allow assignment of different levels of drop precedence to IP packets. This paper examines differentiation predictability and implementation complexity in creation of proportional lossrate (PLR) differentiation between drop precedence levels. PLR differentiation means that fixed loss-rate ratios between different traffic aggregates are provided independent of traffic loads. To provide such differentiation, running estimates of loss-rates can be used as feedback to keep loss-rate ratios fixed at varying traffic loads. In this paper, we define a loss-rate estimator based on average drop distances (ADDs). The ADD estimator is compared with an estimator that uses a loss history table (LHT) to calculate loss-rates. We show, through simulations, that the ADD estimator gives more predictable PLR differentiation than the LHT estimator. In addition, we show that a PLR dropper using the ADD estimator can be implemented efficiently.

  • 15.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Drop strategies and loss-rate differentiation2001In: Proceedings: Ninth International Conference on Network Protocols, ICNP 2001 : 11 - 14 November 2001, Riverside, California, USA, Los Alamitos, Calif: IEEE Communications Society, 2001, p. 146-154Conference paper (Refereed)
    Abstract [en]

    When offering loss-rate differentiation in IP networks, the drop strategy used can have a considerable influence on packet loss and delay. In particular, a strategy of dropping packets only as they arrive can cause bursty loss patterns and high jitter. When only arriving packets are dropped, the router may need to wait for low priority packets to arrive before dropping any packet. This results in larger queue oscillation than if low priority packets were dropped immediately from the queue. Queue oscillation gives bursty loss patterns and delay jitter. We present simulations showing that dropping packets from the queue gives smoother loss patterns and less jitter than if packets are dropped only as they arrive. These simulations cover both TCP Sack and TCP Reno. WRED with and without the gentle modification is used to make drop decisions.

    Download full text (pdf)
    FULLTEXT01
  • 16.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology. Telia research AB, Luleå, Sweden.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology. Swedish Institute of Computer Science (SICS), Kista, Sweden.
    Pink, Stephen
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    Load-tolerant differentiation with active queue management2000In: Computer communication review, ISSN 0146-4833, E-ISSN 1943-5819, Vol. 30, no 3, p. 4-16Article in journal (Refereed)
    Abstract [en]

    Current work in the IETF aims at providing service differentiation on the Internet. One proposal is to provide loss differentiation by assigning levels of drop procedence to IP packets. In this paper, we evaluate the active queue management (AQM) mechanisms RED In and Out (RIO) and Weighted RED (WRED) in providing levels of drop precedence under different loads. For low drop precedence traffic, FIO and WRED can be configured to offer sheltering (i.e., low drop precedence traffic is protected from losses caused by higher drop precedence traffic). However, if traffic control fails or is inaccurate, such configurations can cause starvation of traffic at high drop precedence levels. Configuring WRED to instead offer relative differentiation can eliminate the risk of starvation. However, WRED cannot, without reconfiguration, both offer sheltering when low drop precedence traffic is properly controlled and avoid starvation at overload of low drop precedence traffic. To achieve this, we propose a new AQM mechanism, WRED with Thresholds (WRT). The benefit of WRT is that, without reconfiguration, it offers sheltering when low drop precedence traffic is properly controlled and relative differentiation otherwise. We present simulations showing that WRT has these properties.

  • 17.
    Bodin, Ulf
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Vemmervik, Claes
    Operax AB.
    End-to-End QoS control architectures from a wholesale and retail perspective: benefits and challenges2006Conference paper (Refereed)
    Download full text (pdf)
    FULLTEXT01
  • 18.
    Borg, Niklas
    et al.
    Telia Research AB.
    Svanberg, Emil
    Telia Research AB.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Efficient multi-field packet classification for QoS purposes1999In: 1999 Seventh International Workshop on Quality of Service: IWQoS '99, London, England, May 31 - June 4, 1999, Piscataway, NJ: IEEE Communications Society, 1999, p. 109-118Conference paper (Refereed)
    Abstract [en]

    Mechanisms for service differentiation in datagram networks, such as the Internet, rely on packet classification in routers to provide appropriate service. Classification involves matching multiple packet header fields against a possibly large set of filters identifying the different service classes. In this paper, we describe a packet classifier based on tries and binomial trees and we investigate its scaling properties in three QoS scenarios that are likely to occur in the Internet. One scenario is based on integrated services and RSVP and the other two are based on differentiated services. By performing a series of tests, we characterize the processing and memory requirements for a software implementation of our classifier. Evaluation is done using real data sets taken from two existing high-speed networks. Results from the IntServ/RSVP tests on a Pentium 200 MHz show that it takes about 10.5 μs per packet and requires 2000 KBytes of memory to classify among 11000 entries. Classification for a virtual leased line service based on DiffServ with the same number of entries takes about 9 μs per packet and uses less than 250 KBytes of memory. With an average packet size of 2000 bits, our classifier can manage data rates of about 200 Mbit/s on a 200 MHz Pentium. We conclude that multi-field classification is feasible in software and that high-performance classifiers can run on low-cost hardware

    Download full text (pdf)
    FULLTEXT01
  • 19.
    Börjesson, Mikael
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Nilsson, Michael
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Nolin, Marie
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Distance- Spanning Technology.
    Project: Cloudberry Datacenters2014Other (Other (popular science, discussion, etc.))
  • 20.
    Chiquito, Alex
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Access Control Model for Time Series Databases using NGAC2020In: Proceedings: 2020 25th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA), IEEE, 2020, p. 1001-1004Conference paper (Refereed)
    Abstract [en]

    In Industry 4.0 and Industrial Internet of Things (IIoT), large amounts of time-series sensor data is collected from devices and machines. Industrial data typically contain sensitive information that may harm the data owner should it leaks. Although such risks exist, selected data frequently needs to be shared in partner eco-systems to take advantage of expertise in analyzing the data and to synchronize between partners collaborating in the production system. Consequently, access control must support efficient data selection and sharing. The access control should be capable of managing and enforcing access policies for different operations and with different levels of granularity, while being simple to properly maintain and potentially automate. In this paper we examine the possible use of Next-Generation Access Control (NGAC) for such access control. NGAC is an attribute-based access control (ABAC) standard based on relations between data elements to create, manage and enforce access control policies. We propose an Access control model that maps the NGAC policy language to thequerylanguageoftime-seriesdatabasestofacilitateasecure and efficient data sharing system for IIoT sensor data

    Download full text (pdf)
    fulltext
  • 21.
    Chiquito, Alex
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Attribute-Based Approaches for Secure Data Sharing in Industrial Contexts2023In: IEEE Access, E-ISSN 2169-3536, Vol. 11, p. 10180-10195Article in journal (Refereed)
    Abstract [en]

    The sharing of data is becoming increasingly important for the process and manufacturing industries that are using data-driven models and advanced analysis to assess production performance and make predictions, e.g., on wear and tear. In such environments, access to data needs to be accurately controlled to prevent leakage to unauthorized users while providing easy to manage policies. Data should further be shared with users outside trusted domains using encryption. Finally, means for revoking access to data are needed. This paper provides a survey on attribute-based approaches for access control to data, focusing on policy management and enforcement. We aim to identify key properties provided by attribute-based access control (ABAC) and attribute-based encryption (ABE) that can be combined and used to meet the abovementioned needs.We describe such possible combinations in the context of a proposed architecture for secure data sharing. The paper concludes by identifying knowledge gaps to provide direction to future research on attribute-based approaches for secure data sharing in industrial contexts.

    Download full text (pdf)
    fulltext
  • 22.
    Chiquito, Alex
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Automated Management of Attribute-Based Policies for Access Control using Tag-Matching2023In: IECON 2023 - 49th Annual Conference of the IEEE Industrial Electronics Society, Institute of Electrical and Electronics Engineers (IEEE), 2023Conference paper (Refereed)
    Abstract [en]

    Data sharing is becoming increasingly important as organizations seek to improve their operations and gain a competitive advantage. The data sharing between organizations, stakeholders, and even internal teams requires access control policies that define who can access what data, under what circumstances, and for what purposes.Attribute-based access control (ABAC) provides a flexible and fine-grained mechanism for enforcing such policies, preventing data leakage, and improving security and compliance. A challenge is that these policies should be able to support the agility and adaptability of constantly evolving modern industrial systems, where new data sources, services, and users are frequently added and removed.  As the number of data sources and associated policies grows, the manual management of ABAC policies in evolving systems becomes a bottleneck, which prevents the adoption of fine-grained access control mechanisms. This paper presents a model based on tag-matching to automate the process of connecting new data sources and users to existing access control policies. In the proposed model, tag-matching means matching metadata elements to policy attributes to reduce the administrative work of managing access policies. The model takes advantage of the identity abstraction of ABAC policies to connect existing rules between attributes and the target resource or user. We present a proof-of-concept implementation of the tag-matching model in Eclipse Arrowhead and provide an evaluation of the proposed solution. 

    Download full text (pdf)
    fulltext
  • 23.
    Chiquito, Alex
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science. Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Evaluation of an Attribute-Based Encryption enabled Attribute-Based Access Control ArchitectureManuscript (preprint) (Other academic)
    Abstract [en]

    Decentralized data repositories and external cloud-based services are pivotal in facilitating industrial data sharing, but they often come with administrative overhead. These solutions provide the scalability and accessibility needed for efficient storage and sharing of industrial data, enhancing collaboration and data-driven decision-making while ensuring data security. In this paper, we explore means to combine Attribute-based Access Control and Attribute-based Encryption (ABE). We propose an innovative approach to secure data sharing at rest and at transit with low administrative and management overhead. The solution leverages ABE's ability to encrypt data with fine-grained policies while keeping ABAC's flexibility and ease of management. We provide an evaluation of our solution and discuss the results in the context of industrial data-sharing use cases and applications. Moreover, we provide design guidelines for implementation. Our findings provide valuable insights into the effectiveness of ABE in preserving data privacy during the data-sharing process. Importantly, this is achieved without introducing significant time complexity, even when considering factors like policy size and the number of attributes involved. Furthermore, our study demonstrates that these benefits can be realized while still maintaining the ease of management and the fine-grained control inherent in ABAC schemes.

  • 24.
    Chiquito, Alex
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Fine-grained Access Control for Time-Series Databases using NGAC2021In: Proceedings: 2021 IEEE 19th International Conference on Industrial Informatics (INDIN), IEEE, 2021Conference paper (Refereed)
    Abstract [en]

    Industrial Internet of Things (IIoT) and Industry 4.0 rely heavily on data for reasons such as production follow-up, planning and optimization. Industrial data come in large volumes from production logs and sensors whereof some data carries business and strategic value, sensitive information, or a combination of both. Such data must be protected from unauthorized access, but also be easy to access for authorized users to facilitate work to gain business and operational values from the data. The efficient creation and maintenance of access policies for secure data sharing is hence essential, but unfortunately also challenging in terms of the complexity and administrative effort for fine-grained such. Attribute-based access control (ABAC) such as the Next Generation Access Control (NGAC) provides efficient models for handling access policies. Existing access control models fail however to provide a simple and easy-to-maintain policy language capable of efficiently enforcing fine-grained access control policies for large volumes of time-series data. In this paper, we propose extensions to NGAC based on filter strings that facilitates efficient enforcement of row-level value and time constraint policies for time-series data. We evaluate two approaches for storing and retrieving these filter strings and provide a qualitative and quantitative discussion of the results.

  • 25.
    Chiquito, Eric
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Survey on Decentralized Auctioning Systems2023In: IEEE Access, E-ISSN 2169-3536, Vol. 11, p. 51672-51688Article in journal (Refereed)
    Abstract [en]

    An electronic auction (e-auction) is an efficient negotiation model that allows multiple sellers or buyers to compete for assets or rights. Such systems have become increasingly popular with the evolution of the internet for commerce. In centralized auctioning systems, the presence of a governing third party has been a major trust concern, as such a party may not always be trustworthy or create transaction fees for the hosted auctions. Distributed and decentralized systems based on blockchain for auctions of nonphysical assets have been suggested as a means to distribute and establish trust among peers, and manage disputes and concurrent entries. Although a blockchain system provides attractive features such as decentralized trust management and fraud prevention, it cannot alone support dispute resolutions and adjudications for physical assets. In this paper, we compare blockchain and non-blockchain decentralized auctioning systems based on the identified functional needs and quality attributes. We contrast these needs and attributes with the state-of-the-art models and other implementations of auctioning systems, and discuss the associated trade-offs. We further analyze the gaps in the existing decentralized approaches and propose design approaches for decentralized auctioning systems, for both physical and nonphysical assets, that support dispute resolution and adjudication based on collected evidence, and dispute prevention based on distributed consensus algorithms.

  • 26.
    Degermark, Mikael
    et al.
    Luleå University of Technology.
    Köhler, Torsten
    Luleå University of Technology. Swedish Institute of Computer Science, Kista, Sweden.
    Pink, Stephen
    Luleå University of Technology. Swedish Institute of Computer Science, Kista, Sweden.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Advance reservations for predictive service1995In: Network and Operating Systems Support for Digital Audio and Video: Proceedings of the 5th International Workshop on Network and Operating System Support for Digital Audio and Video / [ed] Thomas D C Little; Riccardo Gusella, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 1995, p. 1-15Conference paper (Refereed)
    Abstract [en]

    We extend a measurement-based admission control algorithm suggested for predictive service to provide advance reservations for guaranteed and predictive service while keeping the attractive features of predictive service. The admission decision for advance reservations is based on information about flows that overlap in time. For flows that have not yet started, the requested values are used, and for those that have already started measurements are used. This allows us to estimate the network load accurately for the near future. To provide advance reservations we ask users to include durations in their requests. We provide simulation results to show that predictive service with advance reservations provides utilization levels significantly higher than those for guaranteed service.

  • 27.
    Degermark, Mikael
    et al.
    Luleå University of Technology.
    Köhler, Torsten
    Luleå University of Technology. Swedish Institute of Computer Science, Kista, Sweden.
    Pink, Stephen
    Luleå University of Technology. Swedish Institute of Computer Science, Kista, Sweden.
    Schelén, Olov
    Swedish Institute of Computer Science, Kista, Sweden.
    Advance reservations for predictive service in the Internet1997In: Multimedia Systems, ISSN 0942-4962, E-ISSN 1432-1882, Vol. 5, no 3, p. 177-186Article in journal (Refereed)
    Abstract [en]

    We extend a measurement-based admission control algorithm suggested for predictive service to provideadvance reservations for guaranteed and predictive service.while retaining the attractive features of predictive service.The admission decision for advance reservations is based oninformation about flows that overlap in time. For flows thathave not yet started, the requested values are used, and forthose that have already started measurements are used. Thisallows us to estimate the network load accurately for thenear future. To provide advance reservations we ask usersto include durations in their requests. We present simulationresults to show that predictive service with advance reservations provides utilization levels significantly higher thanthose for guaranteed service, and comparable to those forpredicted service without advance reservations. Those utilization levels are reached without any preemption of otheradmitted flows. Finally, we discuss how to setup advancereservations over multiple hops in the Internet using resourcereservation setup protocols.

    Download full text (pdf)
    fulltext
  • 28.
    Dudin, Alexander
    et al.
    BSU.
    Osipov, Evgeny
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Dudin, Sergey
    BSU.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Socio-behavioral scheduling of time-frequency resources for modern mobile operators2013In: Modern Probabilistic Methods for Analysis of Telecommunication Networks: Belarusian Winter Workshops in Queueing Theory, BWWQT 2013, Minsk, Belarus, January 28-31, 2013. Proceedings, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2013, p. 69-82Conference paper (Refereed)
    Abstract [en]

    This article presents a mathematical foundation for scheduling of batch data produced by mobile end users over the time-frequency resources provided by modern mobile operators. We model the mobile user behavior by Batch Markovian Arrival Process, where a state corresponds to a specific user data activity (i.e. sending a photo, writing a blog message, answering an e-mail etc). The state transition is marked by issuing a batch of data of the size typical to the activity. To model the changes of user behavior caused by the environment, we introduce a random environment which affects the intensities of transitions between states (i.e., the probabilities of the user data activities). The model can be used for calculating probability of packet loss and probability of exceeding the arbitrarily fixed value by the sojourn time of a packet in the system conditional that the packet arrives to the system at moments when the random environment has a given state. This allows to compute the realistic values of these probabilities and can help to properly fix their values that can be guaranteed, depending on the state of the random environment, by a service provider

  • 29.
    Engan, M.
    et al.
    Luleå University of Technology.
    Fransson, Pierre
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Selective truncating internetwork protocol: experiments with explicit framing2000In: Proceedings: Ninth International Conference on Computer Communications and Networks : 16 - 18 October 2000, Las Vegas, Nevada / [ed] Ton Engbersen, Piscataway, NJ: IEEE Communications Society, 2000, p. 220-224Conference paper (Refereed)
    Abstract [en]

    Many emerging real-time applications generate layered data streams, which can be used effectively to adapt multicast real-time transmissions to heterogeneous bandwidth environments. However, these applications have not changed with regard to being sensitive to transient congestion and cannot wait a full round-trip time for sender-initiated adaptation. In this paper we propose the selective truncating internetwork protocol (STRIP) supporting layered data transfer, and capable of handling congestion at a finer level of granularity by truncating packets, i.e., stripping off less important data. STRIP inter-operates with the traditional IP infrastructure and can be introduced in a step-by-step fashion, starting where the benefits are obvious, for example with routers which are connected to bandwidth constrained links and which have a surplus of processing capacity. We describe the design and architecture of STRIP and compare it with solutions for differentiated forwarding on a per-packet basis. STRIP provides a simple mechanism that can meet the demands for real-time flows effectively by supporting low delay forwarding, avoiding data-unit reordering, and supporting various drop priorities at the same time

    Download full text (pdf)
    FULLTEXT01
  • 30.
    Fink, Christoffer
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Krutrök, Wilma
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Layout planning in assembly line kitting - a constraint programming approach2021In: 2021 26th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA), IEEE, 2021, p. 1-8Conference paper (Refereed)
    Abstract [en]

    In truck manufacturing, an assembly line is typically used to produce many models and variations of trucks in any desired order. Thus, stations are fed with specific sets of parts, known as kits, depending on what truck is next in line. This paper focuses on how to automate the layout planning for placing parts on a kitting wagon. Layout planning resembles the pallet loading problem, but differences include that there is no layering, there may be constraints on how each part can be placed (orientation) and there may be predefined layout hints suggesting positions. A layout planner based on constraint programming is presented. The objective is to facilitate a decision support loop where an engineer may add placement hints as constraints (e.g., for enhancing the workflow at assembly stations) and reuse placements from similar kits to provide recognition. The layout planner automatically generates layout proposals. Finally, it is the engineer that approves the layout plan. There may be many acceptable solutions that have different scores (i.e., levels of quality). We show some approaches to reduce the search space to improve performance. The evaluations show the score and time needed for finding results on some problem instances that are optimally solvable. In the general case, however, finding an optimal solution may be unnecessary or even intractable.

  • 31.
    Forsgren, Nils-Olof
    et al.
    Luleå University of Technology.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    An interactive proof system for test congruence between processes1988Licentiate thesis, comprehensive summary (Other academic)
    Download full text (pdf)
    fulltext
  • 32.
    Idowu, Samuel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Saguna, Saguna
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Applied Machine Learning: Forecasting Heat Load in District Heating System2016In: Energy and Buildings, ISSN 0378-7788, E-ISSN 1872-6178, Vol. 133, p. 478-488Article in journal (Refereed)
    Abstract [en]

    Forecasting energy consumption in buildings is a key step towards the realization of optimized energy production, distribution and consumption. This paper presents a data driven approach for analysis and forecast of aggregate space and water thermal load in buildings. The analysis and the forecast models are built using district heating data unobtrusively collected from ten residential and commercial buildings located in Skellefteå, Sweden. The load forecast models are generated using supervised machine learning techniques, namely, support vector machine, regression tree, feed forward neural network, and multiple linear regression. The model takes the outdoor temperature, historical values of heat load, time factor variables and physical parameters of district heating substations as its input. A performance comparison among the machine learning methods and identification of the importance of models input variables is carried out. The models are evaluated with varying forecast horizons of every hour from 1 up to 48 hours. Our results show that support vector machine, feed forward neural network and multiple linear regression are more suitable machine learning methods with lower performance errors than the regression tree. Support vector machine has the least normalized root mean square error of 0.07 for a forecast horizon of 24 hour.

  • 33.
    Idowu, Samuel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Saguna, Saguna
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Forecasting Heat Load for Smart District Heating Systems: A Machine Learning Approach2014In: 2014 IEEE International Conference on Smart Grid Communications (SmartGridComm 2014): Venice, 3-6 Nov. 2014, Piscataway, NJ: IEEE Communications Society, 2014, p. 554-559Conference paper (Refereed)
    Abstract [en]

    The rapid increase in energy demand requires effective measures to plan and optimize resources for efficient energy production within a smart grid environment. This paper presents a data driven approach to forecasting heat load for multi- family apartment buildings in a District Heating System (DHS). The forecasting model is built using six and eleven weeks of data from five building substations. The external factors and internal factors influencing the heat load in substations are parameters used as our model’s input. Short-term forecast models are generated using four supervised Machine Learning (ML) techniques: Support Vector Regression (SVR), Regression Tree, Feed Forwards Neural Network (FFNN) and Multiple Linear Regression (MLR). Performance comparison among these ML methods was carried out. The effects of combining the internal and external factors influencing heat load at substations was studied. The models are evaluated with varying horizon up to 24-hours ahead. The results show that SVR has the best accuracy of 5.6% MAPE for the best-case scenario.

    Download full text (pdf)
    FULLTEXT01
  • 34.
    Idowu, Samuel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Machine learning in district heating system energy optimization2014In: 2014 IEEE International Conference on Pervasive Computing and Communications workshops: PERCOM WORKSHOPS 2014, Budapest, Hungary; 24-28 March 2014, Piscataway, NJ: IEEE Communications Society, 2014, p. 224-227, article id 6815206Conference paper (Refereed)
    Abstract [en]

    This paper introduces a work in progress, where we intend to investigate the application of Reinforcement Learning (RL) and online Supervised Learning (SL) to achieve energy optimization in District-Heating (DH) systems. We believe RL is an ideal approach since this task falls under the control-optimization problem where RL has yielded optimal results in previous work. The magnitude and scale of a DH system complexity incurs the curse of dimensionalities and model, hereby making RL a good choice since it provides a solution for the problem. To assist RL even further with the curse of dimensionalities, we intend to investigate the use of SL to reduce the state space. To achieve this, we shall use historical data to generate a heat load sub-model for each home. We believe using the output of these sub-models as feedback to the RL algorithm could significantly reduce the complexity of the learning task. Also, it could reduce convergence time for the RL algorithm. The desired goal is to achieve a realtime application, which takes operational actions when it receives new direct feedback. However, considering the dynamics of DH system such as large time delay and dissipation in DH network due to various factors, we hope to investigate things such as the appropriate data sampling rate and new parameters / sensors that could improve knowledge about the state of the system, especially on the consumer side of the DH network.

  • 35.
    Idowu, Samuel
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brännström, Robert
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Machine Learning in Pervasive Computing2013Report (Other academic)
    Abstract [en]

    Increase in data quantities and number of pervasive systems has resulted in many decision-making systems. Most of these systems employ Machine Learning (ML) in various practical scenarios and applications. Enormous amount of data generated by sensors can be useful in decision-making systems. The rising number of sensor driven pervasive systems presents interesting research areas on how to adapt and apply existing ML techniques effectively to the domain of pervasive computing. In the face of data deluge, ML has proved viable in many application areas such as data mining and self-customizing programs and could bring about great impact in the field of pervasive computing.The objective of this study is to give the underlying concepts of ML techniques that can be applied to problems in the domain of pervasive and mobile computing. The scope of this study covers the three primary types of ML, supervised, unsupervised and reinforcement learning methods. In the process of providing the fundamental knowledge of ML, we present some conceptual terms of ML and the steps required in developing ML system with a great impact on domains outside ML scope.Our findings show that previous works in the area of ubiquitous computing have successfully applied supervised learning and reinforcement learning methods. Hence, this study focuses more on supervised learning and reinforcement learning. In conclusion, we discuss some basic performance evaluation metrics and methods for obtaining reliable classifiers estimates, such as cross-validation and leave-one-out validation.

    Download full text (pdf)
    FULLTEXT01
  • 36.
    Jimenez, Lara Lorna
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Simon, Miguel Gomez
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Kristiansson, Johan
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Synnes, Kåre
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Åhlund, Christer
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    CoMA: Resource Monitoring of Docker Containers2015In: Proceedings of the 5th International Conference on Cloud Computing and Services Science (CLOSER 2015), SCITEPRESS Digital Library , 2015, Vol. 1, p. 145-154Conference paper (Refereed)
    Abstract [en]

    This research paper presents CoMA, a Container Monitoring Agent, that oversees resource consumption of operating system level virtualization platforms, primarily targeting container-based platforms such as Docker. The core contribution is CoMA, together with a quantitative evaluation verifying the validity of the measurements reported by the agent for three metrics: CPU, memory and block I/O. The proof-of-concept is implemented for Docker-based systems and consists of CoMA, the Ganglia Monitoring System and the Host sFlow agent. This research is in line with the rising trend of container adoption which is due to the resource efficiency and ease of deployment. These characteristics have set containers in a position to topple virtual machines as the reigning virtualization technology in data centers.

  • 37.
    Jiménez, Lara Lorna
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    DOCMA: A Decentralized Orchestrator for Containerized Microservice Applications2019In: 2019 3rd IEEE International Conference on Cloud and Fog Computing Technologies and Applications: IEEE Cloud Summit 2019, Washington, D.C., USA, USA: IEEE, 2019, p. 45-51Conference paper (Refereed)
    Abstract [en]

    The advent of the Internet-of-Things and its associated applications are key business and technological drivers in industry. These pose challenges that modify the playing field for Internet and cloud service providers who must enable this new context. Applications and services must now be deployed not only to clusters in data centers but also across data centers and all the way to the edge. Thus, a more dynamic and scalable approach toward the deployment of applications in the edge computing paradigm is necessary. We propose DOCMA, a fully distributed and decentralized orchestrator for containerized microservice applications built on peer-to-peer principles to enable vast scalability and resiliency. Secure ownership and control of each application are provided that do not require any designated orchestration nodes in the system as it is automatic and self-healing. Experimental results of DOCMA's performance are presented to highlight its ability to scale.

  • 38.
    Jiménez, Lara Lorna
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    HYDRA: Decentralized Location-aware Orchestration of Containerized Applications2022In: IEEE Transactions on Cloud Computing, ISSN 2168-7161, Vol. 10, no 4, p. 2664-2678Article in journal (Refereed)
    Abstract [en]

    The edge computing paradigm, spurred by the Internet-of-Things, poses new requirements and challenges for distributed application deployment. There is a need for an orchestrator design that leverages characteristics that enable this new paradigm. We present HYDRA, a decentralized and distributed orchestrator for containerized microservice applications. This orchestrator focuses on scalability and resiliency to enable the global manageability of cloud and edge environments. It can manage heterogeneous resources across geographical locations and provide robust application control. Further, HYDRA enables the location-aware deployment of microservice applications via containerization. Thus, an application's services may be deployed to separate locations according to expected needs. In this paper, the experiments show the orchestrator scaling to 20 000 nodes and simultaneously deploying 30 000 applications. Further, empirical results show that location-aware application deployment does not hinder HYDRA's performance, and the random resource search algorithm currently being employed may be used as a baseline to find resources in this decentralized orchestrator. Therefore, we conclude that HYDRA is a viable orchestrator design for the new computing paradigm.

  • 39.
    Karlsson, Johan
    et al.
    Luleå University of Technology.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Brodnik, Andrej
    Nilsson, Andreas
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Extended expedited forwarding: the in-time PHB group2003In: Computers and Communication, 2003. (ISCC 2003): Proceedings of the Eighth IEEE International Symposium on Computers and Communications, IEEE Computer Society Press , 2003, Vol. 1, p. 291-298Conference paper (Refereed)
    Abstract [en]

    This paper presents a new set of forwarding behaviorsthat fits rate-adaptive and delay-sensitive applications withlimited loss tolerance. We consider an application to havelimited loss tolerance if it needs loss-free forwarding of specificpackets up to a certain rate. The new set of forwardingbehaviors are attractive for developing real-time applicationsfor the Internet. In particular, such applications canbe designed to use reserved forwarding capacity efficientlyand compete for more bandwidth while being fair to best-efforttraffic. To provide the new set of forwarding behaviors,we define a scheduling mechanism that can be implementedefficiently. Through simulations, we show that thismechanism supports the defined forwarding behaviors.

    Download full text (pdf)
    FULLTEXT01
  • 40. Larzon, Lars-Åke
    et al.
    Bodin, Ulf
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Hints and notifications [for wireless links]2002In: 2002 IEEE Wireless Communications and Networking Conference record: Orlando, Florida, USA, 17 - 21 March 2002, Piscataway, NJ: IEEE Communications Society, 2002, p. 635-641Conference paper (Refereed)
    Abstract [en]

    With current Internet protocols, users may experience low and unpredictable forwarding quality at wireless links. This is due to varying link properties caused by changing radio conditions. Decreased forwarding quality can cause severe degradation in utilization. This is undesirable since forwarding capacity often is expensive at wireless links because of the limited radio spectrum. Allowing the application and transport layers to communicate with wireless link layers can improve the forwarding quality and utilization. We propose to enable inter-layer communication by adding hints and notifications (HAN) to the Internet architecture. Hints can be introduced and used without notifications, while notifications need hints or a similar mechanism to operate. By using IP options and ICMP messages to implement HAN, a backward-compatible partial deployment is possible. With HAN, the network layer becomes truly wireless friendly and the radio spectrum can be used efficiently while supporting both real-time and traditional data applications.

    Download full text (pdf)
    FULLTEXT01
  • 41.
    Lindgren, Anders
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Abdesslem, Fehmi Ben
    SICS Swedish ICT AB.
    Ahlgren, Bengt
    SICS Swedish ICT AB.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Malik, Adeel Mohammad
    Ericsson.
    Design choices for the IoT in Information-Centric Networks2016In: 2016 13th IEEE Annual Consumer Communications & Networking Conference (CCNC): Las Vegas, 9-12 Jan. 2016, Piscataway, NJ: IEEE Communications Society, 2016, p. 882-888, article id 7444905Conference paper (Refereed)
    Abstract [en]

    This paper outlines the tradeoffs involved in utilizing Information-Centric Networking (ICN) for Internet of Things (IoT) scenarios. It describes contexts and applications where the IoT would benefit from ICN, and where a host-centric approach would be better. Requirements imposed by the heterogeneous nature of IoT networks are discussed in terms of connectivity, power availability, computational and storage capacity. Design choices are then proposed for an IoT architecture to handle these requirements, while providing efficiency and scalability. An objective is to not require any IoT specific changes of the ICN architecture per se, but we do indicate some potential modifications of ICN that would improve efficiency and scalability for IoT and other applications

  • 42. Lindgren, Anders
    et al.
    Almquist, A.
    Luleå University of Technology.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Evaluation of quality of service schemes for IEEE 802.11 wireless LANs2001In: Proceedings: LCN 2001, 26th Annual IEEE Conference on Local Computer Networks : 14 - 16 November 2001, Tampa, Fl, Los Alamitos, Calif: IEEE Communications Society, 2001, p. 348-351Conference paper (Refereed)
    Abstract [en]

    This paper evaluates four mechanisms for providing service differentiation in IEEE 802.11 wireless LANs, the point coordinator function (PCF) of IEEE 802.11, the enhanced distributed coordinator function (EDCF) of the proposed IEEE 802.11e extension to IEEE 802.11, distributed fair scheduling (DFS), and Blackburst using the ns-2 simulator. The metrics used in the evaluation are throughput, medium utilization, collision rate, average access delay, and delay distribution for a variable load of real time and background traffic. The PCF performance is comparably low, while the EDCF performs much better. The best performance is achieved by Blackburst. The DFS provides relative differentiation and consequently avoids starvation of low priority traffic

    Download full text (pdf)
    FULLTEXT01
  • 43.
    Lindgren, Anders
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Almquist, Andreas
    Luleå University of Technology.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Quality of service schemes for IEEE 802.11: a simulation study2001In: Quality of Service: 9th International Workshop Karlsruhe, Germany, June 6-8, 2001 Proceedings / [ed] Lars Wolf, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2001, p. 281-287Conference paper (Refereed)
    Abstract [en]

    This paper analyzes and compares four different mechanisms for providing QoS in IEEE 802.11 wireless LANs. We have evaluated the IEEE 802.11 mode for service differentiation (PCF), Distributed Fair Scheduling, Blackburst, and a scheme proposed by Deng et al. using the ns-2 simulator. The evaluation covers medium utilization, access delay, and the ability to support a large number of high priority mobile stations. Our simulations show that PCF performs badly, and that Blackburst has the best performance with regard to the above metrics. An advantage with the Deng scheme and Distributed Fair Scheduling is that they are less constrained, with regard to the characteristics of high priority traffic, than Blackburst is.

  • 44.
    Lindgren, Anders
    et al.
    Luleå University of Technology.
    Almquist, Andreas
    Luleå University of Technology.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Quality of Service Schemes for IEEE 802.11 Wireless LANs – An Evaluation2003In: Mobile Networks and Applications, ISSN 1383-469X, E-ISSN 1572-8153, Vol. 8, no 3, p. 223-235Article in journal (Refereed)
    Abstract [en]

    This paper evaluates four mechanisms for providing service differentiation in IEEE 802.11 wireless LANs. The evaluated schemes are the Point Coordinator Function (PCF) of IEEE 802.11, the Enhanced Distributed Coordinator Function (EDCF) of the proposed IEEE 802.11e extension to IEEE 802.11, Distributed Fair Scheduling (DFS), and Blackburst. The evaluation was done using the ns-2 simulator. Furthermore, the impact of some parameter settings on performance has also been investigated. The metrics used in the evaluation are throughput, medium utilization, collision rate, average access delay, and delay distribution for a variable load of real time and background traffic. The simulations show that the best performance is achieved by Blackburst. PCF and EDCF are also able to provide pretty good service differentiation. DFS can give a relative differentiation and consequently avoids starvation of low priority traffic.

    Download full text (pdf)
    fulltext
  • 45. Lindgren, Anders
    et al.
    Doria, Avri
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Probabilistic routing in intermittently connected networks2004In: Service Assurance with Partial and Intermittent Resources: First International Workshop, SAPIR 2004, Fortaleza, Brazil, August 1-6, 2004, Proceedings / [ed] Petre Dini; Pascal Lorenz; José Neuman De Souza, Berlin: Encyclopedia of Global Archaeology/Springer Verlag, 2004, p. 239-254Conference paper (Refereed)
    Abstract [en]

    In this paper, we address the problem of routing in intermittently connected networks. In such networks there is no guarantee that a fully connected path between source and destination exists at any time, rendering traditional routing protocols unable to deliver messages between hosts. There does, however, exist a number of scenarios where connectivity is intermittent, but where the possibility of communication still is desirable. Thus, there is a need for a way to route through networks with these properties. We propose PRoPHET, a probabilistic routing protocol for intermittently connected networks and compare it to the earlier presented Epidemic Routing protocol through simulations. We show that PRoPHET is able to deliver more messages than Epidemic Routing with a lower communication overhead

    Download full text (pdf)
    FULLTEXT01
  • 46. Lindgren, Anders
    et al.
    Doria, Avri
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Probabilistic routing in intermittently connected networks2003Conference paper (Other academic)
    Abstract [en]

    We consider the problem of routing in intermittently connected networks. In such networks there is no guarantee that a fully connected path between source and destination exist at any time, rendering traditional routing protocols unable to deliver messages between hosts. We propose a probabilistic routing protocol for such networks.

    Download full text (pdf)
    FULLTEXT01
  • 47. Lindgren, Anders
    et al.
    Doria, Avri
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Routing in intermittently connected networks using a probabilistic approach2003In: Swedish National Computer Networking Workshop - Proceedings: SNCNW 2003, Stockholm, 2003Conference paper (Other academic)
    Abstract [en]

    In this paper we consider the problem of routing in intermittently connected networks. In such networks there is no guarantee that a fully connected path between source and destination exists at any time, rendering traditional routing protocols unable to deliver messages between hosts. There do however exist a number of scenarios where connectivity is intermittent, but where the possibility of communication still is desirable. Thus, there is a need for a way to route through such networks. We propose PROPHET, a probabilistic routing protocol for such networks and compare it to the earlier presented Epidemic Routing protocol through simulations. We show that PROPHET is able to deliver more messages than Epidemic Routing with a lower communication overhead.

    Download full text (pdf)
    FULLTEXT01
  • 48. Lindgren, Anders
    et al.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Infrastructured ad hoc networks2002In: International Conference on Parallel Processing Workshops: 18 - 21 August 2002, Vancouver, B.C., Canada ; proceedings / [ed] Stephan Olariu, Los Alamitos, Calif: IEEE Communications Society, 2002, p. 64-70Conference paper (Refereed)
    Abstract [en]

    In traditional ad hoc networks, all nodes are considered equal and take equal part in the routing and forwarding of packets. We believe that this may not always be desirable. Rather, some nodes may be equipped with virtually unlimited power supplies, while others have to rely on battery power Thus, we propose the creation of "infrastructured" ad hoc networks by the deployment of pseudo base-stations (PBSs), which are nodes that have constant power supply (e.g., through a power outlet or a car battery), do not move, and are present just to act as routers and forward packets for other nodes, thus allowing the mobile nodes to save power The paper also presents ISAIAH, an ad hoc routing protocol based on the ad-hoc on-demand distance vector (AODV) routing protocol, which tries to select routes that go through PBSs instead of through mobile nodes to reduce the amount of power spent by these mobile nodes. Furthermore, it allows nodes to enter a power-saving mode, significantly reducing the power consumption compared to AODV

    Download full text (pdf)
    FULLTEXT01
  • 49.
    Monrat, Ahmed Afif
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab. Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    A Taxonomy Guideline for Blockchain PlatformsIn: Journal of Wireless Mobile Networks, Ubiquitous Computing, and Dependable Applications (JoWUA), ISSN 2093-5374Article in journal (Refereed)
    Abstract [en]

    Conventional approaches to agreeing on transactions in monetary systems rely on trusted central authorities. Blockchain defies this model by achieving consensus through a community of peers in a decentralized network for validating transactions and maintaining an ordered record of transactions. The application domains for blockchain have expanded from cryptocurrencies to potentially any industrial system. However, there is still a lot of confusion regarding the advantage of using the blockchain instead of alternative technologies. The number of successfully deployed blockchain-based systems is still relatively small due to the lack of clarity regarding blockchain governance and the challenge of assessing the tradeoffs of blockchain-based solutions. As there are different types of blockchains, such as permissionless and permissioned, it often becomes hard to choose a suitable solution for a specific use case scenario. In this paper, we address these challenges by analyzing blockchain governance and related tradeoffs, including energy consumption, consensus, performance, and security. We contribute with a taxonomy guideline to provide insights on these tradeoffs and to facilitate effective identification of the suitable governance structure for blockchain-based solutions in various scenarios. The proposed taxonomy discusses different features of blockchain that includes energy consumption, consensus methods, performance, and security aspects to suggest the governance model (permissionless/permissioned/consortium) for a blockchain-based solution. Furthermore, this paper provides a tradeoff analysis of different consensus methods, such as PoW, PoS, PBFT, and PoA, considering important properties.

  • 50.
    Monrat, Ahmed Afif
    et al.
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Schelén, Olov
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Embedded Internet Systems Lab.
    Andersson, Karl
    Luleå University of Technology, Department of Computer Science, Electrical and Space Engineering, Computer Science.
    Addressing the Performance of Blockchain by Discussing Sharding Techniques2023In: Proceedings of 3rd International Conference on Electrical, Computer, Communications and Mechatronics Engineering (ICECCME), IEEE, 2023Conference paper (Refereed)
    Abstract [en]

    Blockchain technology is extensively used for cryptocurrencies and is considered for industrial applications due to features like decentralization, anonymity, and a tamper-proof history of transactions. However, the well-known blockchain trilemma of being unable to simultaneously meet the properties of decentralization, security, and scalability (DSS) negatively impacts widespread acceptance. Numerous solutions have been put forward in response to this challenge, aiming to increase performance and scalability while retaining the decentralized and trustless aspects. They range from introducing off-chain technologies to changing consensus algorithms and on-chain data structures. One of the most effective methods to accomplish horizontal scalability along with the growing network size could be sharding, which involves dividing the network of nodes into numerous shards or channels. The overhead of repetitive communication, storage, and processing at each node is decreased by this technique. This paper explores various sharding approaches to solve performance issues regarding blockchain. We review recent sharding technologies, including Polkadot, Ethereum Casper, and Cardano Hydra. We discuss the performance challenges of blockchains and provide essential insights into the tradeoffs.

12 1 - 50 of 83
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf