Identifying Security-Critical Cyber-Physical Components in Industrial Control Systems

In recent years, Industrial Control Systems (ICS) have become an appealing target for cyber attacks, having massive destructive consequences. Security metrics are therefore essential to assess their security posture. In this paper, we present a novel ICS security metric based on AND/OR graphs that represent cyber-physical dependencies among network components. Our metric is able to efficiently identify sets of critical cyber-physical components, with minimal cost for an attacker, such that if compromised, the system would enter into a non-operational state. We address this problem by efficiently transforming the input AND/OR graph-based model into a weighted logical formula that is then used to build and solve a Weighted Partial MAX-SAT problem. Our tool, META4ICS, leverages state-of-the-art techniques from the field of logical satisfiability optimisation in order to achieve efficient computation times. Our experimental results indicate that the proposed security metric can efficiently scale to networks with thousands of nodes and be computed in seconds. In addition, we present a case study where we have used our system to analyse the security posture of a realistic water transport network. We discuss our findings on the plant as well as further security applications of our metric.Comment: Keywords: Security metrics, industrial control systems, cyber-physical systems, AND-OR graphs, MAX-SAT resolutio

Semantic Mediation in Smart Water Networks

Water Distribution Networks (WDN) are the infrastructures responsible for delivering drinking water to consumers. The effective monitoring and control of these systems is of vital importance since malfunction may significantly affect the health, safety, security and/or economic well-being of people. The advancements in coupling WDN with the ICT infrastructure, combined with the more recent introduction of smart sensing and actuation technologies, have enabled the enhancement of "Supervisory Control And Data Acquisition (SCADA)"-based applications. These applications in current water systems assume pre-defined configuration and characteristics of the involved components (sensors, actuators, controllers, etc.). This work explores how semantic mediation techniques may contribute to the online configuration of the monitoring and control architectures by exploiting and reasoning over the capabilities of deployed devices

Covariance patterns between ramus morphology and the rest of the face: A geometric morphometric study

OBJECTIVE The growth and development of the mandible strongly depend on modeling changes occurring at its ramus. Here, we investigated covariance patterns between the morphology of the ramus and the rest of the face. METHODS Lateral cephalograms of 159 adults (55 males and 104 females) with no history of orthodontic treatment were collected. Geometric morphometrics with sliding semi-landmarks was used. The covariance between the ramus and face was investigated using a two-block partial least squares analysis (PLS). Sexual dimorphism and allometry were also assessed. RESULTS Differences in the divergence of the face and anteroposterior relationship of the jaws accounted for 24.1% and 21.6% of shape variation in the sample, respectively. Shape variation was greater in the sagittal plane for males than for females (30.7% vs. 17.4%), whereas variation in the vertical plane was similar for both sexes (23.7% for males and 25.4% for females). Size-related allometric differences between the sexes accounted for the shape variation to a maximum of 6% regarding the face. Regarding the covariation between the shapes of the ramus and the rest of the face, wider and shorter rami were associated with a decreased lower anterior facial height as well as a prognathic mandible and maxilla (PLS 1, 45.5% of the covariance). Additionally, a more posteriorly inclined ramus in the lower region was correlated with a Class II pattern and flat mandibular plane. CONCLUSIONS The width, height, and inclination of the ramus were correlated with facial shape changes in the vertical and sagittal planes

The Embodiment of Intangible Investment Goods: A Q-Theory Approach

Recent empirical findings on firms' expenditure towards the creation and acquisition of knowledge goods, otherwise known as intangibles, suggest that their share in overall investment has grown considerably. Still, intangible investment is rarely present in investment models. In this paper, I extend the q-theory of investment to model explicitly the decision of firms to invest in intangibles. I then use the model to measure the contribution of intangible goods to the overall capital stock in the U.S. The model highlights the embodiment of intangible goods in tangibles and the role of relative price movements in the measurement of the contribution of each type of investment to the overall capital stock. In particular, given that the relative cost of the main input to intangible production, skilled labor, rose substantially in the 80s and 90s, the price of intangibles inherits this rise. As a result, the downward trend in the aggregate investment deflator series reported by national accounts, which accounts only for the presence of tangible investment goods, is found to have a significant downward bias in the 90s. The model also shows that the growth in the overall capital stock from the late-80s until 2000 was driven mainly by an increase in the contribution of intangibles. However, the contribution of intangibles fell consistently after 2000. These results underscore the importance of accounting for the movements in the price of intangibles rather than focusing only on their rising share in overall investment

Battle of the Attack Detection Algorithms:Disclosing cyber attacks on water distribution networks

The BATtle of the Attack Detection ALgorithms (BATADAL) is the most recent competition on planning and management of water networks undertaken within the Water Distribution Systems Analysis Symposium. The goal of the battle was to compare the performance of algorithms for the detection of cyber-physical attacks, whose frequency increased in the past few years along with the adoption of smart water technologies. The design challenge was set for C-Town network, a real-world, medium-sized water distribution system operated through Programmable Logic Controllers and a Supervisory Control And Data Acquisition (SCADA) system. Participants were provided with datasets containing (simulated) SCADA observations, and challenged with the design of an attack detection algorithm. The effectiveness of all submitted algorithms was evaluated in terms of time-to-detection and classification accuracy. Seven teams participated in the battle and proposed a variety of successful approaches leveraging data analysis, model-based detection mechanisms, and rule checking. Results were presented at the Water Distribution Systems Analysis Symposium (World Environmental & Water Resources Congress), in Sacramento, on May 21-25, 2017. This paper summarizes the BATADAL problem, proposed algorithms, results, and future research directions

Placement of synchronized measurements for power system observability

This paper presents a method for the use of synchronized measurements for complete observability of a power system. The placement of phasor measurement units (PMUs), utilizing time-synchronized measurements of voltage and current phasors, is studied in this paper. An integer quadratic programming approach is used to minimize the total number of PMUs required, and to maximize the measurement redundancy at the power system buses. Existing conventional measurements can also be accommodated in the proposed PMU placement method. Complete observability of the system is ensured under normal operating conditions as well as under the outage of a single transmission line or a single PMU. Simulation results on the IEEE 14-bus, 30-bus, 57-bus, and 118-bus test systems as well as on a 298-bus test system are presented in this paper

EPANET-MATLAB Toolkit: Example Code (based on CCWI 2016 publication)

Source-code for executing the case study in our CCWI 2016 pape

The stock market and capital accumulation: an application to UK data

Because of the difficulty in measuring investment in intangible assets and frequent data revisions, estimates based on National Accounts investment data provide an imperfect measure of the capital stock. Following the influential work by Robert Hall for the United States, this paper provides an alternative measure of the UK capital stock based on asset prices. This market-based measure reflects the premise that in fair-valued financial markets the value of firms' securities reflects the value of their productive assets. In line with Hall's results for the United States, the paper suggests that for a range of adjustment costs, depreciation rates and starting values, market-based estimates of the UK capital stock have differed substantially from those based on National Accounts investment data. Despite some advantages over National Accounts based measures, market-based measures are likely to be more volatile, because financial markets' assessment of the value of intangible assets can potentially change rapidly. Nevertheless, they can be a useful cross-check of the National Accounts based measures of the UK capital stock.