The DEXs specify the information to be exchanged and shared in order to support the life cycles of complex assets. The DEXs identify coherent subsets of ISO 10303-239 Product Life Cycle Support (PLCS) that support data flows needed for specific business processes.

The OASIS PLCS Technical Committee is responsible for defining, developing, testing, and publishing of OASIS PLCS DEXs, and for liaison with ISO TC 184/SC4 More information about the OASIS PLCS TC can be found in the OASIS section.

OASIS PLCS TC Publications are derived from the content that is developed (by the TC) on DEXlib. However, it is the publication that is the subject of standardisation, not DEXlib, which is a development environment for the OASIS PLCS TC.

The DEXlib repository of DEXs and their supporting components is organized as follows:

• DEXs: An index of all the DEXs;
  A DEX identifies and documents a subset of the ISO 10303-239 (PLCS) information model required for a specific business purpose;
• Templates: An index of all the Templates;
  The usage of the PLCS information model by a DEX is defined through templates. The templates provide a precise specification of how the model is used to represent a given concept;
• Capabilities: An index of all the Capabilities;
  Capabilities provide guidance on how the information model and templates should be used.
• Business DEXs: An index of all the Business DEXs.
  These are DEXs developed for a specific business domain. They are not standardized through OASIS but are presented here for information and as examples of PLCS usage. They are grouped into Business contexts that define the business domain;
• Reference data: An index of the Reference Data used by the DEXs;
  Reference data provides a tailorable vocabulary that adds business specific semantics to the information model.
• Schemas: An index of the AP239 schema and the DEX schemas, both as EXPRESS models and XML Schemas.

NOTE    For a summary of these components and inter relationships, see "DEX technology overview".

In addition to the components listed above, DEXlib also includes the PLCS Help and Information pages that are provided to explain:

• the business benefits and the technical composition of PLCS and the OASIS PLCS DEXs;
• how a DEX is developed; and
• how implementation of DEX based software is achieved.

The PLCS DEX Help and Information Pages are divided up into the following sections:

• A table of contents of the help and information pages (also available as a menu);
• Navigation instructions: provides an explanation of how to navigate the site;
• DEXlib overview: provides a summary of the concepts used;
• PLCS business overview: provides a business level introduction;
• Technical description of PLCS: provides a technical introduction;
• Instructions for DEX developers: provides instructions for developers of existing or new DEXs;
• Instructions for software implementers: provides technical information for implementers of software that conform to the DEXs.