Research Outputs

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Now showing 1 - 10 of 23
  • Publication
    A Self-Organising Approach for Smart Meter Communication Systems
    (2014) ;
    Skopik, F. 
    ;
    Hutchison, D. 
    ;
    Bleier, T. 
      147  2Scopus© Citations 1
  • Publication
    Generic Autonomic Management as a Service in a SOA-based Framework for Industry 4.0
    (IEEE, 2019-10) ; ;
    Delsing, Jerker 
    Cyber-physical production systems are engineered systems that are built from, and depend upon, the seamless integration of computational algorithms and physical components. In order to make these systems interoperable with each other for addressing Industry 4.0 applications a number of service-oriented architecture frameworks are developed. Such frameworks are composed by a number of services, which are inherently dynamic by nature and thus imply the need for self-adaptation. In this paper we propose generic autonomic management as a service and show how it can be integrated in the Arrowhead framework. We propose generic and reusable interfaces for each phase of the autonomic control loop in order to increase the usability of the service for other frameworks and application systems, while reducing the software engineering effort. To show the utility of our approach in the Arrowhead framework we use a climate control application as a representative example.
      424  1Scopus© Citations 10
  • Publication
    The Case for Heterogeneous WLAN Environments for Converged Networks
    (2013) ;
    Bhatti, S. N. 
    ;
    Melnikov, N. 
    ;
    Schoenwaelder, J. 
      105  1
  • Publication
    Towards Energy-Awareness in Managing Wireless LAN Applications
    (2012) ;
    Bhatti, S. N. 
    ;
    Yu, Y. 
    We have investigated the scope for enabling WLAN applications to manage the trade-off between performance and energy usage. We have conducted measurements of energy usage and performance in our 802.11n WLAN testbed, which operates in the 5 GHz ISM band. We have defined an effective energy usage envelope with respect to application-level packet transmission, and we demonstrate how performance as well as the effective energy usage envelope is effected by various configurations of IEEE 802.11n, including transmission power levels and channel width. Our findings show that the packet size and packet rate of the application flow have the greatest impact on application-level energy usage, compared to transmission power and channel width. As well as testing across a range of packet sizes and packet rates, we emulate a Skype flow, a YouTube flow and file transfers (HTTP over Internet and local server) to place our results in context. Based on our measurements we discuss approaches and potential improvements of management in effective energy usage for the tested applications.
      113  1Scopus© Citations 14
  • Publication
    Towards a Security-Aware Benchmarking Framework for Function-as-a-Service
    In a world, where complexity increases on a daily basis the Function-as-a-Service (FaaS) cloud model seams to take countermeasures. In comparison to other cloud models, the fast evolving FaaS increasingly abstracts the underlying infrastructure and refocuses on the application logic. This trend brings huge benefits in application and performance, but comes with difficulties for benchmarking cloud applications. In this position paper, we present an initial investigation of benchmarking FaaS in close to reality production systems. Furthermore, we outline the architectural design including the necessary benchmarking metrics. We also discuss the possibility of using the proposed framework for identifying security vulnerabilities.
      229  1Scopus© Citations 3
  • Publication
    Towards a Security Cost Model for Cyber-Physical Systems
    (IEEE, 2019-01) ;
    Mauthe, Andreas 
    ;
    In times of Industry 4.0 and cyber-physical systems (CPS) providing security is one of the biggest challenges. A cyber attack launched at a CPS poses a huge threat, since a security incident may affect both the cyber and the physical world. Since CPS are very flexible systems, which are capable of adapting to environmental changes, it is important to keep an overview of the resulting costs of providing security. However, research regarding CPS currently focuses more on engineering secure systems and does not satisfactorily provide approaches for evaluating the resulting costs. This paper presents an interaction-based model for evaluating security costs in a CPS. Furthermore, the paper demonstrates in a use case driven study, how this approach could be used to model the resulting costs for guaranteeing security.
      468  1Scopus© Citations 4
  • Publication
    Application Level Energy and Performance Measurements in a Wireless LAN
    (2011) ;
    Bhatti, S. N. 
    ;
    Yu, Y. 
    We present an experimental evaluation of energy usage and performance in a wireless LAN cell based on a test bed using the 5 GHz ISM band for 802.11a and 802.11n. We have taken an application-level approach, by varying the packet size and transmission rate at the protocol level and evaluating energy usage across a range of application transmission rates using both large and small packet sizes. We have observed that both the application's transmission rate and the packet size have an impact on energy efficiency for transmission in our test bed. We also included in our experiments evaluation of the energy efficiency of emulations of YouTube and Skype flows, and a comparison with Ethernet transmissions.
      141  1Scopus© Citations 24
  • Publication
    Security Vulnerabilities And Risks In Industrial Usage Of Wireless Communication
    (2014-09-16)
    Plosz, S. 
    ;
    Lesjak, C. 
    ;
    Pereira, N. 
    ;
    ;
    Ruprechter, T. 
    Due to its availability and low cost, the use of wireless communication technologies increases in domains beyond the originally intended usage areas, e.g. M2M communication in industrial applications. Such industrial applications often have specific security requirements. Hence, it is important to understand the characteristics of such applications and evaluate the vulnerabilities bearing the highest risk in this context. We present a comprehensive overview of security issues and features in existing WLAN, NFC and ZigBee standards, investigating the usage characteristics of these standards in industrial environments. We apply standard risk assessment methods to identify vulnerabilities with the highest risk across multiple technologies. We present a threat catalogue, conclude in which direction new mitigation methods should progress and how security analysis methods should be extended to meet requirements in the M2M domain.
      135  1Scopus© Citations 24