Concurrent software engineering: coordinating distributed viewpoints for managing inconsistency

Concurrent engineering involves the collaboration and coordination of a physically distributed team with variable opportunities for communication with one another. Traditional approaches to the problems of distributed working use a central database, or repository, to which all team members have communication access. Consistency is managed in this database through strict access control and version management, along with a common data model or schema. Such centralised approaches do not adequately support the reality of distributed engineering, where communication with a central database cannot always be guaranteed, and access control rapidly becomes a bottleneck. The alternative, a fully decentralised environment, is seen to be problematic because of the difficulties of maintaining consistency between a large collection of agents. However, these problems can be overcome by recognising that maintaining global consistency at all times is an unnecessary burden. Indeed, it is often desirable to tolerate and even encourage inconsistency, to maximise design freedom, and to prevent premature commitment to design decisions. The focus therefore shifts from maintaining consistency to the management of inconsistencies