[Approaches to modelling of interdependencies between critical infrastructure]

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ACKNOWLEDGEMENT

I would take this opportunity to thank my research supervisor, family and friends for their support and guidance without which this research would not have been possible

DECLARATION

I, [type your full first names and surname here], declare that the contents of this dissertation/thesis represent my own unaided work, and that the dissertation/thesis has not previously been submitted for academic examination towards any qualification. Furthermore, it represents my own opinions and not necessarily those of the University.

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ABSTRACT

The study of the interdependencies within critical infrastructures (CI) is a growing field of research as the importance of potential failure propagation among infrastructures may lead to cascades affecting all supply networks. New powerful methods are required to model and describe such ''systems-of systems'' (SoS) as a whole. An overall model is required to provide security and reliability assessment taking into account various kinds of threats and failures. A significant challenge associated with this model may be to create ''what-if'' scenarios for the analysis of interdependencies. In this paper the interdependencies between industrial control systems (ICS), in particular SCADA (Supervisory Control and Data Acquisition), and the underlying critical infrastructures to address the vulnerabilities related to the coupling of these systems are analyzed. The modelling alternatives for system-of-systems, integrated versus coupled models, are discussed. An integrated model contains detailed low level models of (sub)systems as well as a high level model, covering all hierarchical levels. On the other hand, a coupled model aggregates different simulated outputs of the low level models as inputs at a higher level. Strengths and weaknesses of both approaches are analyzed and a model architecture for SCADA and the ''system under control'' are proposed. Furthermore, the HLA simulation standard is introduced and discussed in this paper as a promising approach to represent interdependencies between infrastructures. To demonstrate the capabilities of the HLA standard for the interdependencies study, an exemplary application and some first results are also briefly presented in this paper.

TABLE OF CONTENTS

ACKNOWLEDGEMENTII

DECLARATIONIII

ABSTRACTIV

CHAPTER 1: INTRODUCTION AND OBJECTIVES1

Background of the project1

Problem Statement4

Aims & Objectives of the project5

Rationale of the Project5

Significance of the Project10

CHAPTER 2: ENGAGEMENT WITH ACADEMIC LITERATURE17

CHAPTER 3: METHODS43

CHAPTER 4: RESULTS46

CHAPTER 5: DISCUSSION49

CHAPTER 6: EVALUATION, REFLECTIONS, AND CONCLUSIONS54

REFERENCES56

CHAPTER 1: INTRODUCTION AND OBJECTIVES

Background of the project

In this paper we study critical infrastructures, analyzing them at the single system level and the system-of-systems level, and evaluate advanced modelling and simulation techniques that are required to gain a fundamental understanding of the behaviour of these types of infrastructures. Classical reliability theories are well established and widely used to model large complicated systems. Stochastic models, e.g. the Markov and Poisson processes , are being applied to predict the behaviour of systems that include uncertainties, but these methods lack the capability to completely capture the underlying structure of the system and the ability to adapt to failures of subsystems when strong interdependencies exist . There is a lack of models to capture the interaction of complex adaptive systems, such as the electric power grid and automation ...