Towards operational measures of computer security

Ideally, a measure of the security of a system should capture quantitatively the intuitive notion of ‘the ability of the system to resist attack’. That is, it should be operational, reflecting the degree to which the system can be expected to remain free of security breaches under particular conditions of operation (including attack). Instead, current security levels at best merely reflect the extensiveness of safeguards introduced during the design and development of a system. Whilst we might expect a system developed to a higher level than another to exhibit ‘more secure behaviour’ in operation, this cannot be guaranteed; more particularly, we cannot infer what the actual security behaviour will be from knowledge of such a level. In the paper we discuss similarities between reliability and security with the intention of working towards measures of ‘operational security’ similar to those that we have for reliability of systems. Very informally, these measures could involve expressions such as the rate of occurrence of security breaches (cf rate of occurrence of failures in reliability), or the probability that a specified ‘mission’ can be accomplished without a security breach (cf reliability function). This new approach is based on the analogy between system failure and security breach. A number of other analogies to support this view are introduced. We examine this duality critically, and have identified a number of important open questions that need to be answered before this quantitative approach can be taken further. The work described here is therefore somewhat tentative, and one of our major intentions is to invite discussion about the plausibility and feasibility of this new approach

Securing the Elderly: A Developmental Approach to Hypermedia-Based Online Information Security for Senior Novice Computer Users

Whilst security threats to the general public continue to evolve, elderly computer users with limited skill and knowledge are left playing catch-up in an ever-widening gap in fundamental cyber-related comprehension. As a definable cohort, the elderly generally lack awareness of current security threats, and remain under-educated in terms of applying appropriate controls and safeguards to their computers and networking devices. This paper identifies that web-based computer security information sources do not adequately provide helpful information to senior citizen end-users in terms of both design and content

Patterns of information security postures for socio-technical systems and systems-of-systems

This paper describes a proposal to develop patterns of security postures for computer based socio-technical systems and systems-of-systems. Such systems typically span many organisational boundaries, integrating multiple computer systems, infrastructures and organisational processes. The paper describes the motivation for the proposed work, and our approach to the development, specification, integration and validation of security patterns for socio-technical and system-of-system scale systems

Towards Security Requirements in Online Summative Assessments

Confidentiality, integrity and availability (C-I-A) are the security requirements fundamental to any computer system. Similarly, the hardware, software and data are important critical assets. These two components of a computer security framework are entwined; such that a compromise in the C-I-A requirements may lead to a compromise of the critical assets. The C-I-A requirements and the critical assets of a computer system are well researched areas; however they may be insufficient to define the needs of a summative e-assessment system. In this paper, we do not discard the existing components; rather we propose security requirements and related components that are specific to summative e-assessment systems