Publication Process

Publications of the VEC follow a defined pattern. Which documents are distributed for a VEC version depends on the type of release. The following release types are used. The type of release is reflected in the version numbering pattern:

Release Types

Major Releases

Theses releases are normally integrating a significant amount of changes. They can be identified in a change of the first or second digit of the version number (e.g. 1.1 vs. 1.0). These releases are always accompanied by the release of a new version of the recommendation document.

Bugfix and Feature Releases

Bugfix and Feature Releases are published in between the major releases. They are used to allow a timely response on feature requests and bug reports, especially from ongoing implementation projects. These releases can be published more frequently, since such releases have a more lean process.

Distributed Artefacts

For each version several artefacts are distributed:

  1. VDA Recommendation and / or prostep ivip Recommendation (only for Major Releases)
  2. An updated Model Description (Online and/or as PDF): This description is contained in the VDA Recommendation.
  3. XML Schema Files which are available in different variants:
    • strict vs. non-strict: The non-strict schema variant defines OpenEnumerations as xs:string values. In the strict schema variant OpenEnumerations are defined as schema restrictions. For more information about the OpenEnumerations see the corresponding chapter in the VDA Recommendation. The strict schema variant carries the suffix -strict in the file name of the schema.
    • documented vs. undocumented (since VEC 1.1.3): For an improved usability of the schema, the model documentation (description of classes and attributes) is embedded in the schema files. For use cases where the size of the schema file matters, we provide variants of the schema files without embedded documentation. Those are marked with the suffix -ud for “undocumented”.
  4. Schematron-Schema: Version 1.1.3 was published together with a schematron schema. On the basis of the findings in this “beta”-phase, this approach will not be pursued further. However, it is undeniable that additional semantic rules apply in addition to pure syntactic correctness (checked by the schema). Currently we are looking for appropriate solutions to address this requirement in a way that is suitable for an open industry standard. Reasons for the rejection of the schematron approach were among others:
    • Definition of advanced rules with xpath based on a complex model is cumbersome, hard to maintain and not self descriptive for users of the schema.
    • Insufficient market penetration of the required technology (schema aware XSLT 2 processors).
    • Performance of the base technology XSLT is poor for XML files with the size seen in todays VEC implementations.

Implementation Guidelines / Tutorials

From VEC Version 1.1.3 on, the Implementation Guidelines (a.k.a Tutorials) will no longer be published as a versioned single document, but as a collection of pages for specific topics in this WIKI. The intention of this is to provide tutorials / implementation guidelines for specific topics within a shorter timeframe. The entrypoint for the Implementation Guidlines can be found here: VEC Implementation Guidelines