AP203 is formally known as STEP Part 203: Application Protocol for Configuration Controlled Design. The standard was originally published in 1994 and was subsequently amended in 2000 as ISO 10303-203:1994/Amd1:2000(E).

In 2005, it was restructured as a modular document and published as the technical specification ISO/TS 10303-203:2005(E). After further rework, the TS was replaced by a international standard published in 2011 as ISO 10303-203:2011(E). The name was changed to "Configuration controlled 3D design of mechanical parts and assemblies" with a matching EXPRESS schema name.

Programming Notes

The original AP203 schema is identified by the StplibSchemaType stplib_schema_ap203 enum, while the stplib_schema_ap203e2 enum identifies the second edition schema.

RoseDesign * d;

// first edition "CONFIG_CONTROL_DESIGN"
stplib_put_schema (d, stplib_schema_ap203);

stplib_put_schema (d, stplib_schema_ap203e2);

switch (stplib_get_schema(d)) {
case stplib_schema_ap203e2:
    // ap203 second edition, or various interim schemas

case stplib_schema_ap203:
    // ap203 first edition
The following schema names were used between the first and second edition and are recognized as the stplib_schema_ap203e2 enum, but should not be used for new data.
This name was used for the interim 2005 Technical Specification (not International Standard) version of AP203.
These two names were used during CAX-IF construction history (SMCH) testing which apparently made it into some versions of Pro-Engineer and Ideas.

The following recommended practices document covers the original AP203 schema and is still useful for basic topics like assembly relationships. More recommended practices are available on the CAx-IF site for things introduced in AP203e2 and AP242.

Deprecated Definitions

The original AP203 was the first AP, and used naming conventions that later changed. Assignment entities had a "cc_design_" prefix, while newer APs use the "applied_" prefix. The "cc_design" were deprecated in the second edition and replaced with the "applied" versions (See AP203e2 annex H). The original schema also had subtypes for contexts but now APs just use the base types.

The STEP Merged AP Library only contains "applied_" definitions. When working with older files, we read "cc_design" data into instances of the "applied" C++ classes, and write "applied" definitions as the appropriate "cc_design" name.

The table below shows the changes. When reading an AP203 file, an entity in the left column is will appear in memory as an instance of the type on the right. When writing a file as AP203, an instance of a type on the right will be written as the type on the left.

AP203 Definition Merged Library Definition

Deprecated AP203 assignments, automatically remapped to applied types

cc_design_approval applied_approval_assignment
cc_design_certification applied_certification_assignment
cc_design_contract applied_contract_assignment
cc_design_date_and_time_assignment applied_date_and_time_assignment
cc_design_person_and_organization_assignment applied_person_and_organization_assignment
cc_design_security_classification applied_security_classification_assignment
cc_design_specification_reference applied_document_reference

Deprecated AP203 context subtypes, automatically remapped to supertypes

mechanical_context product_context
design_context product_definition_context

Deprecated, but still present in the schema.

advanced_brep_representation An old definition, which was used in AP203 files that predate the 1994 publication of AP203 and AIC 514. Same data as advanced_brep_shape_representation but has no name field, so we make it a standalone entity instead of a representation subtype. Manually convert to the newer representation if found in a file.

Deprecated, but still present in the schema.

change unchanged, AP203 design activity model deprecated
change_request unchanged, AP203 design activity model deprecated
change_request_item unchanged, AP203 design activity model deprecated
design_make_from_relationship unchanged, AP203 design activity model deprecated
document_with_class unchanged, deleted in AP203e2
ordinal_date unchanged
product_definition_formation_with_specified_source unchanged, previously required by AP203 CC1
start_request unchanged, AP203 design activity model deprecated
start_request_item unchanged, AP203 design activity model deprecated
start_work unchanged, AP203 design activity model deprecated
supplied_part_relationship unchanged, AP203 design activity model deprecated
week_of_year_and_day_date unchanged
work_item unchanged, but AP203 design activity model deprecated

Retired/Merged SELECT types

Do not appear in Part 21 files, but the names might be used in older C++ code written for AP203. The "cc_" prefix definitions are legacy things that were renamed in AP203e2 and AP242

approved_item approval_item
certified_item certification_item
classified_item When updating AP203 code, change to security_classification_item. Later APs used this name for group assignments (applied_classification_assignment)
cc_classified_item security_classification_item
contracted_item contract_item
date_time_item date_and_time_item
person_organization_item person_and_organization_item
cc_person_organization_item person_and_organization_item
specified_item document_reference_item
cc_specified_item document_reference_item