The implementation guidelines and recommendations provided in this document are aimed to close the gap between the JT specification (JT DIN SPEC and ISO 14306) and “real world” implementation tasks. They are also aimed towards vendors with the objective to provide recommendations how to best implement certain aspects of the JT standards, by itself or in combination with accompanying formats such as STEP AP242 XML. The recommendations given in this document have been discussed intensively, and agreed on, by the JT Implementor Forum members and will be implemented by them as a means of enhancing interoperability of application using the JT format.

This document understands itself as a complement to the following documents:

• The JT File Format specification (currently: ISO 14306:2017; 2017-11), which defines the data model and file format itself.
• The JT DIN SPEC 91383:2018-09, JT Industrial Application Package (JTIAP), which defines the syntax and semantics of the JT file format and is compatible to the JT file format specification in ISO 14306 (in its version from 2012 and successors) as well as to the essential implementations currently available to the market.
• The JT Content Harmonization guideline (currently: version 2.1; 2012-12-07), which gives recommendations about property names (keys), property values, and configuration settings to be applied by users.

Consequently, the JT Implementation Guideline stands between the two documents listed above, as it gives additional information on the implementation of the JT File Format specification where the group feels the given information is not sufficient, or ambiguous. It is aimed towards the implement_x0002_ers of JT translators and documents agreements on a technical level. The JT Content Harmonization guideline, on the other hand, is aimed towards users and documents agreements on the levels of process and content. The issues mentioned here were raised by one of the following bodies:

• During the ISO ballot
• prostep ivip / VDA JT Workflow Forum
• prostep ivip / VDA JT Implementor Forum