3 - Objectives
There has been little work relating dependability and configurability, and there is opportunity for DIRC to make a significant contribution in this area.
A socio-technical system comprises: (a) social processes that utilise (b) computer-based systems to provide a service. The overall system
is often consists of sub-systems that comprise both computer systems and associated social processes. Our hypothesis is that:
- Reasonably frequent, non-catastrophic failures of sub-systems are
common in these systems. That many of these failures are repaired
without loss of service, but there may be a degradation in service,
- That the evolution of the system initiates new failures, and
- That the control of these failures is often dealt with by measures,
e.g. reconfiguration both of the computer systems and the social processes,
- These measures often lead to significant improvements in dependability
Lack of dependability can be of economic and social importance, and the consequences of failure can be serious . Socio-technical systems
have several distinguishing characteristics. Here we concentrate on three:
- Failure resilience: often sub-system failure is of little immediate
consequence, but coping with such failures can be costly and consequences
of neglect can be serious. Sub-system failures are often reasonably
frequent and coping with failure can require effort. Failure frequency
provides data the help direct the design and deployment processes.
- Evolution: socio-technical systems are dynamic: the requirements
on the system, context of use and common practice can change significantly
over time. Mechanisms are needed to detect change and realign socio-technical
systems to changed circumstances.
- Configuration: critical in the deployment and evolution of socio-technical
systems. During and after deployment designers need to understand
how well the system is suited to use, and users to understand aspects
of the design in order to configure them, often way in which a system
is "tuned" to meet its dependability requirements.
Our goal is to develop approaches that address these features of socio-technical
systems, addressing commercial uptake to maximise applicability, and
taking account of:
- Integration with standard commercial development processes, e.g.
the Unified Process, various agile processes.
- Progressive application of our techniques depending on the required
level of dependability.
- The need for tool support; without which effective diversification
of evidence necessary to design socio-technical systems is unlikely.
- Progress towards a situation where
- Dependability targets for complex socio-technical systems can
be expressed meaningfully.
- These targets can be achieved predictably through design and
- Data on dependability be measured effectively and verifiably,
and these. measurements can help direct the configuration process.
Dependability can be maintained and improved after deployment as the
requirements and the socio-technical system evolve. Objectives are therefore:
- To observe the long-term user-led evolution and reconfiguration
of socio-technical systems in situ, and to analyse how these processes
both cope with, and may be sources of system failure.
- To devise and assess approaches to configuration in socio-technical
systems to avoid, control and manage non-catastrophic sub-system failures.
- To devise and assess evidence-driven approaches in supporting both
developers and users in achieving dependability requirements, in particular,
exploring lightweight methods based on data gathering to direct the