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Mili, Ali

Publications and source records attributed to Mili, Ali.

9 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2014

Quantifying Availability in SCADA Environments Using the Cyber Security Metric MFC

Supervisory Control and Data Acquisition (SCADA) systems are distributed networks dispersed over large geographic areas that aim to monitor and control industrial processes from remote areas and/or a centralized location. They are used in the management of critical infrastructures such as electric power generation, transmission and distribution, water and sewage, manufacturing/industrial manufacturing as well as oil and gas production. The availability of SCADA systems is tantamount to assuring safety, security and profitability. SCADA systems are the backbone of the national cyber-physical critical infrastructure. Herein, we explore the definition and quantification of an econometric measure of availability, as it applies to SCADA systems; our metric is a specialization of the generic measure of mean failure cost.

Availability↗
DOE OSTI2014

Quantifying the Impact of Unavailability in Cyber-Physical Environments

The Supervisory Control and Data Acquisition (SCADA) system discussed in this work manages a distributed control network for the Tunisian Electric & Gas Utility. The network is dispersed over a large geographic area that monitors and controls the flow of electricity/gas from both remote and centralized locations. The availability of the SCADA system in this context is critical to ensuring the uninterrupted delivery of energy, including safety, security, continuity of operations and revenue. Such SCADA systems are the backbone of national critical cyber-physical infrastructures. Herein, we propose adapting the Mean Failure Cost (MFC) metric for quantifying the cost of unavailability. This new metric combines the classic availability formulation with MFC. The resulting metric, so-called Econometric Availability (EA), offers a computational basis to evaluate a system in terms of the gain/loss ($/hour of operation) that affects each stakeholder due to unavailability.

Availability↗
DOE OSTI2013

Risk Assessment Methodology Based on the NISTIR 7628 Guidelines

Earlier work describes computational models of critical infrastructure that allow an analyst to estimate the security of a system in terms of the impact of loss per stakeholder resulting from security breakdowns. Here, we consider how to identify, monitor and estimate risk impact and probability for different smart grid stakeholders. Our constructive method leverages currently available standards and defined failure scenarios. We utilize the National Institute of Standards and Technology (NIST) Interagency or Internal Reports (NISTIR) 7628 as a basis to apply Cyberspace Security Econometrics system (CSES) for comparing design principles and courses of action in making security-related decisions.

Algorithms↗
DOE OSTI2013

Failure Impact Analysis of Key Management in AMI Using Cybernomic Situational Assessment (CSA)

In earlier work, we presented a computational framework for quantifying the security of a system in terms of the average loss a stakeholder stands to sustain as a result of threats to the system. We named this system, the Cyberspace Security Econometrics System (CSES). In this paper, we refine the framework and apply it to cryptographic key management within the Advanced Metering Infrastructure (AMI) as an example. The stakeholders, requirements, components, and threats are determined. We then populate the matrices with justified values by addressing the AMI at a higher level, rather than trying to consider every piece of hardware and software involved. We accomplish this task by leveraging the recently established NISTR 7628 guideline for smart grid security. This allowed us to choose the stakeholders, requirements, components, and threats realistically. We reviewed the literature and selected an industry technical working group to select three representative threats from a collection of 29 threats. From this subset, we populate the stakes, dependency, and impact matrices, and the threat vector with realistic numbers. Each Stakeholder s Mean Failure Cost is then computed.

Algorithms↗
DOE OSTI2013

U.S. Patent Pending, Cyberspace Security System for Complex Systems, U.S. Patent Application No.: 14/134,949

A computer implemented method monetizes the security of a cyber-system in terms of losses each stakeholder may expect to lose if a security break down occurs. A non-transitory media stores instructions for generating a stake structure that includes costs that each stakeholder of a system would lose if the system failed to meet security requirements and generating a requirement structure that includes probabilities of failing requirements when computer components fails. The system generates a vulnerability model that includes probabilities of a component failing given threats materializing and generates a perpetrator model that includes probabilities of threats materializing. The system generates a dot product of the stakes structure, the requirement structure, the vulnerability model and the perpetrator model. The system can further be used to compare, contrast and evaluate alternative courses of actions best suited for the stakeholders and their requirements.

Availablity↗
DOE OSTI2012

Defining and Computing a Valued Based Cyber-Security Measure

In earlier work, we presented a value based measure of cybersecurity that quantifies the security of a system in concrete terms, specifically, in terms of how much each system stakeholder stands to lose (in dollars per hour of operation) as a result of security threats and system vulnerabilities; our metric varies according to the stakes that each stakeholder has in meeting each security requirement. In this paper, we discuss the specification and design of a system that collects, updates, and maintains all the information that pertains to estimating our cybersecurity measure, and offers stakeholders quantitative means to make security-related decisions.

Algorithms↗
NASA NTRS2000

Modeling the Fault Tolerant Capability of a Flight Control System: An Exercise in SCR Specification

In life-critical and mission-critical applications, it is important to make provisions for a wide range of contingencies, by providing means for fault tolerance. In this paper, we discuss the specification of a flight control system that is fault tolerant with respect to sensor faults. Redundancy is provided by analytical relations that hold between sensor readings; depending on the conditions, this redundancy can be used to detect, identify and accommodate sensor faults.

Alexander, Chris↗