A unifying model for consistent distributed software development environments

The increase in size and complexity of software projects over recent years has lead to the need for Software Development Environments (SDEs). SDEs are intended to provide assistance in the development of large software systems involving teams of people. It is generally agreed that SDE's should be built on a distributed base. However, the distribution of computer systems introduces several problems which make it very difficult to maintain the consistency of data. To ensure that changes to data are made consistently the concept of atomic transactions is usually adopted. However, existing transaction mechanisms are unsuitable for use in a distributed SDE. Furthermore, transactions are not the only mechanism concerned with controlling changes to the SDE database. The control of change is also a task for version and configuration control mechanisms. Traditionally, the functions of version control, configuration control and transactions have been treated as separate, unrelated issues. This paper presents a new model which unifies all three concepts in a distributed SDE. Mechanisms for supporting the new model are presented and the application of the model to the Cosmos Distributed SDE is discussed.