System Dependibility - Related Papers

Patterns for Dependable Design - David Martin, Mark Rouncefield and Ian Sommerville

The argument for the involvement of social scientists in dependable socio-technical systems design reasons is that, to be dependable, systems need to be appropriate both for the application domain and potential users. Before designers can solve a design problem they need to understand some basics - such as what they are designing, who should use it, how often and in what circumstances (Scherer 2002); social analysis of settings where systems are deployed can expose subtle interactions and practices that are crucial to achieving this understanding but which are not revealed by a more structured, technical analysis.

Martin, D. and Sommerville, I. (2006). Patterns for Dependable Design. In Trust in Technology: A Socio-technical Perspective. Rouncefield, M., Clarke, J., Hardstone, G. and Sommerville, I. (eds.). London: Springer.

Designing for recovery: New challenges for large-scale, complex IT systems - Ian Sommerville

Powerpoint Presentation

Sommerville, I. (2008). Designing for Recovery: New Challenges for Large-Scale Complex IT Systems. In Proceedings of the Seventh International Conference on Composition-Based Software Systems (ICCBSS 2008) (ICCBSS '08). IEEE Computer Society, Washington, DC, USA, 15-. DOI=10.1109/ICCBSS.2008.42 http://dx.doi.org/10.1109/ICCBSS.2008.42

Social Analysis and Dependable Systems Design - Ian Sommerville

Powerpoint Presentation


Sommerville, I. (2007). Social Analysis and Dependable Systems Design. Presented at Curtin University of Technology, Perth WA in February 2007.

Design for failure: Software challenges of digital ecosystems - Ian Sommerville

Powerpoint Presentation


Sommerville, I. (2007). Design for Failure: Software Challenges of Digital Ecosystems. Presented at the 1st IEEE Conference on Digital Ecosystems in Cairns, Australia in February 2007.

A Dependability Model for Domestic Systems
- Guy Dewsbury, Ian Sommerville, Karen Clarke and Mark Rouncefield

Technically-based models of dependability such as Laprie's model suggest that there are attributes that should be reflected in the design of a system. These attributes tend to be attributes of the software or hardware and the models assume that system operators can be treated in the same way as software or hardware components. While this approach may be valid for some control systems with tightly specified operational processes, we argue that it must be extended if it is to be applied to systems where there is significant discretion on the part of the user as to how they will use the system. In particular, for systems in the home, we argue that the notion of dependability should be broadened This paper suggests that through the design of assistive technology (AT) systems for older people we can demonstrate the user should be placed at the centre of the process when considering system dependability.

Sommerville, I., Dewsbury, G., Clarke, K. and Rouncefield, M. (2002). A Dependability Model for Domestic Systems. Proc. SAFECOMP 2003, Edinburgh, September 2003, Springer, 103-15.

Dependable Red Hot Action- Karen Clarke, John Hughes, Dave Martin, Mark Rouncefield, Ian Sommerville

We present a brief observational, ‘ethnographic’, study of the Roughing Mill in a steel plant and use material from recorded activities to provide ‘illustrative vignettes’ of some aspects of the accomplishment and problems of everyday work. The account provides a ‘bottom up’ method for developing a more sophisticated and situated view of the problems of dependability. The paper documents the social organisation of work in the Roughing Mill, the interaction between the computer scheduler and the skill of the mill operator in accomplishing ‘dependable’ production of steel plates from slabs.

Hughes, J. Martin, D., Rouncefield, M. Sommerville, I., Hartswood, M., Procter, R., Slack, R., Voss, A. (2003). Dependable Red-Hot Action. Proc. 8th European Conference on CSCW, September 2003, pp 61-80.

Dependability and Trust in Organisational and Domestic Computer Systems- Ian Sommerville, Guy Dewsbury, Karen Clarke, Mark Rouncefield

Our economy and national infrastructures are dependent on a range of socio-technical systems and, by and large, these systems can be trusted to provide a dependable service. For example, electricity and telecommunication systems are generally reliable, the bank ATM network can usually deliver cash to authorised customers and automated stock control systems have meant that large stores and supermarkets rarely run out of specific products.

Sommerville, I., Dewsbury, G., Clarke, K. and Rouncefield, M. (2006). Dependability and Trust in Organisational and Domestic Computer Systems. In Trust in Technology: A Socio-technical Perspective. Rouncefield, M., Clarke, J., Hardstone, G. and Sommerville, I. (eds.). London: Springer.[Book chapter]


Designing Dependable Digital Domestic Environments
- Guy Dewsbury, Karen Clarke, John Hughes, Mark Rouncefield, and Ian Sommerville

The aim of this paper is to examine the distinctions between home and organizational settings with particular reference to assistive technologies (AT) and outline a model for assessing dependability issues in these environments. For the purposes of this paper we consider assistive technologies to be software-controlled networks of assistive devices. Clearly a home is a personal concept and a social construction, which imbues different meanings to each individual through social actions and the assignment of meaning to those actions. It is therefore important that any method of investigation is sensitive to the changing meanings and nature of people’s conceptions of home. This paper outlines the fundamental concepts used by the Lancaster team and proposes a method of conceptualizing dependability within a home context.
This paper suggests that the design of AT involves a number of factors that can be derived from a number of sources but essentially all design should place the user at the centre of the process. We aim to show that the home is different from the standard organization and as such deserves consideration in its own right and technology systems need to meet certain criteria within domestic situations that are not covered within traditional organizations. We extend this notion by considering the use of AT in terms of previous models of design and assessment. We also acknowledge that older people are not a homogenous category, and that designing for a group requires sensitivity to the individual needs of the person rather than the categorization of the person. We then consider the role of systems development and deployment from the perspective of designing AT systems for older people and this brings us to consider the problems that are associated with dependability. We contend that standard dependability analysis falls short of the full picture of analysis when applied to domestic settings.


Clarke, K., Dewsbury, G., Hughes, J., Rouncefield, M. and Sommerville, I. (2003). Designing Dependable Digital Domestic Environments. Proc. HOIT 2003, The Networked Home of the Future Conference, Irvine, California. April 2003.


Appropriate Home Technology: Depending on Dependable Technology Systems
- Guy Dewsbury, Karen Clarke, Mark Rouncefield, and Ian Sommerville

Dwelling with computers, they become part of the informing environment, like weather, like street sounds. A house that is true to its house nature must have a certain quiet, even stolidness. Through a thousand subtle cues, computers will help turn our houses into homes. Weiser (1996)
This paper is interested in explicating some of the multiple concerns involved in designing appropriate technology in domestic, or home, settings. As society becomes increasingly reliant on computer-based systems, and as domestic settings become increasingly technologised, the systems themselves have become increasingly complex and the need for dependable systems correspondingly important. Achieving sufficient dependability in these systems, and demonstrating this achievement in a rigorous and convincing manner, appears crucial in moving towards an inclusive Information Society. The paper reflects our interest in making some initial steps towards developing improved means of specifying, designing, assessing, deploying and maintaining complex socio-technical systems in domestic contexts where high dependability is crucial. As computer-based systems and artefacts penetrate more and more into people’s everyday lives and homes, the ‘design problem’ is not so much concerned with the creation of new technical artefacts as it is with their effective and dependable configuration and integration. It is evident that satisfactory resolution of such concerns demands major, interdisciplinary breakthroughs in understanding the development of complex socio-technical systems in domestic environments since inadequate understanding of the context of the lived reality of use and user needs is often a significant cause of lack of dependability. The paper also explores the ongoing DIRC project which is currently investigating these areas within its Project Activity ‘Dependable Ubiquitous Computing In The Home’. While this paper does not attempt to solve all of the presented issues it aims to illuminate and highlight some fields of investigation that might form the basis for future and ongoing research and development agendas for appropriate technological interventions in domestic settings


Dewsbury, G., Clarke, K., Rouncefield, M., and Sommerville, I. (2002). Appropriate Home Technology: depending on dependable technology systems. Proc. Housing and Health Workshop, ENHR 2002, Vienna, Austria, July 2002.

Dependable Domestic Systems Design: A Socio-technical Approach - I Sommerville, G Dewsbury

This paper describes a model that defines the attributes of domestic systems that lead to system dependability and a user-oriented specification method for support systems based on this model. We start by discussing technical dependability models and discuss how these have to be extended for use in a domestic context. We present an extended dependability model based on a socio-technical perspective. This extends the technical notion of dependability to take into account fitness for purpose, acceptability and adaptability. We then go on to discuss MDDS – a questionnaire-based method that reflects the socio- technical dependability model. It is intended for use by social care professionals who are specifying and designing support systems for older or disabled people. MDDS provides a basis for examining a design from a dependability perspective. We illustrate the use of the method and conclude with a discussion of its qualitative evaluation.

Sommerville, I., Dewsbury, G. Dependable Domestic Systems Design: A Socio-technical Approach. Interacting with Computers. 19 (4), 438–56.

The Effects of Timing and Collaboration on Dependability in the Neonatal Intensive Care Unit - Godon Baxter, Juliana Kuster Filipe, Angela Miguel, Kenneth Tan

Computer-based systems are now routinely deployed in many complex dynamic domains, such as aviation and industrial process control. The critical nature of these systems means that their operators rely on them to do the right thing at the right time when called upon. In other words, they are expected to have a high level of what Laprie (1995) defines as dependability. To date dependability research has largely focused on developing techniques for improving the dependability of hardware and software in safety critical applications (e.g., Leveson, 1995). Dependability, however, is a property of the whole socio-technical system: people, computers and context. It is therefore important not only to understand these components, but also how the interactions between them affect dependability.

Baxter, G.D., Filipe, J.K., Miguel, A., & Tan, K. (2005). The effects of timing and collaboration on dependability in the neonatal intensive care unit. In F. Redmill and T. Anderson (Eds.), Constituents of Modern System-safety Thinking: Proceedings of the Thirteenth Safety-critical Systems Symposium. (pp. 195-210). London, UK: Springer-Verlag.