SystemWeaver is based on fine grained versioning, meaning that all items have a version history and changeability state, or in other terms: all SystemWeaver Items are Configuration Items. This means that individual changes can easily be understood and analyzed, e.g., between two different versions of a requirement specification, it is possible to discern all changes to each individual requirement. This means that if a tester should update a test specification based on changes to the requirements specification, he/she only needs to work with the changed requirements.
The figure below illustrates the different version states of an item:
Whenever a new item is created it is automatically set to Work status, meaning that any user with sufficient rights may change the Item, including its version status. When an item is Frozen or Released no changes may be made to the item. This however means no restriction in the use of the item in a model, i.e. by referring to the item from other items.
Note that the Released state is final. The only way to alter a released item is by creating a new version of the item. Note also that the Frozen state is not final since it may be transitioned into Work using the Thaw operation.
Creation of new versions adds to the version history of the item, which is managed within SystemWeaver:
The versioning operations can be used for versioning of configurations, where the Freeze and Release operations work on the set of items in the configuration.