Models of Reliability of Fault-Tolerant Software Under Cyber-Attacks

Abstract

This is the accepted version of the paper.This version of the publication may differ from the final published version. Abstract -This paper offers a new approach to modelling the effect of cyber-attacks on reliability of software used in industrial control applications. The model is based on the view that successful cyber-attacks introduce failure regions, which are not present in non-compromised software. The model is then extended to cover a fault tolerant architecture, such as the 1-out-of-2 software, popular for building industrial protection systems. The model is used to study the effectiveness of software maintenance policies such as patching and "cleansing" ("proactive recovery") under different adversary models ranging from independent attacks to sophisticated synchronized attacks on the channels. We demonstrate that the effect of attacks on reliability of diverse software significantly depends on the adversary model. Under synchronized attacks system reliability may be more than an order of magnitude worse than under independent attacks on the channels. These findings, although not surprising, highlight the importance of using an adequate adversary model in the assessment of how effective various cyber-security controls are. Permanent repository link:

From Analyzing Operating System Vulnerabilities to Designing Multiversion Intrusion-Tolerant Architectures

“…One of the most challenging parts of the work on applying diversity in practice is the justification of the effectiveness of proposed solutions due to the lack of empirical data. The use of software diversity for security and intrusion-tolerance was proposed in earlier studies reported in [19,20,21,22], which clearly showed the needs for demonstrating the applicability of the proposed architectural solutions and for evaluating their advantages to drive their design.…”

Low-Code Engineering for the Internet of Things

“…The reliability analysis is additional to the existing State Based Quantitative Dependability Analysis. It exploits Mobius's powerful and well-supported analysis capabilities as an engine for safety and security co-engineering, according to the scenario addressed in [117]. Editing Mobius models can be nontrivial, CHESS modeling language fully supports the modeling of system architectures taking into consideration safety and security co-engineering for reliability analysis with MOBIUS.…”

Hierarchically defining Internet of Things security: From CIA to CACA

“…A system is fault-tolerant, if it can provide normal services, even facing the failures of one or more components. [16][17][18] Fault tolerance reduces the risk induced by random errors. Generally, a fault-tolerance system has the following basic characteristics: (1) all single points cannot fail simultaneously; (2) it must be equipped with mechanisms to isolate the failure components and prevent the spread of failure.…”