The Virtual Data Toolkit (VDT) serves both as the Grid middleware for the international Virtual Data Grid Laboratory (iVDGL) and as a mechanism for testing and dissemination of virtual-data software developed by the GriPhyN project. As a result the VDT simultaneously serves both as a production-level software infrastructure and as a research-level collection of software and tools.
In order to fulfill both roles noted above the VDT working group releases two separate but related versions of the VDT; a stable version and the development version.
The contents of stable and development releases is discussed in detail below. Each release is numbered as X.Y.Z-n where
This scheme and the numbering pattern used to represent the two different versions is based on the scheme used by the Linux kernel developers.
Those using the VDT as the Grid middleware at an iVDGL production site should use the stable release series.
The stable release series contains only those components that are themselves full production releases from their respective development groups or related packagers, or those that have been thoroughly tested and will soon become full production releases.
In addition the stable release series contains only those components that have undergone interoperability testing to verify that all the components are compatible.
New components of the VDT are not introduced into the stable release series until they have first been introduced as part of the development series. This is true even if a component is itself already a production release.
A new stable release is made whenever a component or components in a development release have matured to production, or when a development release into which a production component or compoments have been released has undergone thorough interoperability testing. It is not necessary for every component to have evolved and it is expected that some components will not change between stable releases. The VDT working group makes every effort to test newly introduced or matured components on a timely basis.
A new release in the stable series is made for bug fixes provided that the fix is deemed critical or essential, though the bug fix must have first been released as part of the development series.
A component is not removed from the VDT until it has first been removed from a development series. No component or components will be removed without the removal first being scheduled and announced on the VDT web pages.
Details of the interoperability tests performed are posted on the VDT web pages before or concurrent with a release in the stable series and changes between releases are fully documented on the VDT web pages.
The development release series is intended for those sites that use the VDT as Grid middleware but which need a new component, components, or a pre-production version of a component for reasons of testing, benchmarking, or development.
The development release series contains any components requested by VDT user groups and the GriPhyN developers. Any requested component will be contained in a development release provided there is a reasonable assurance of interoperability with other components. No thorough interoperability testing is done for development releases and no tests are published on the VDT web pages.
A development release may contain multiple new components or updates to components. Development releases are made as often as is warranted and is possible for the VDT team. All changes within a development release may not be documented though the VDT team makes a best effort to note all changes.
A component may be removed from the VDT development series without notification provided the component is not part of the current stable series.