ASN.1 Identifier

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Current Status

1. Most (all?) parts of ISO 10303 directly refer to ISO/IEC 8824-1 Information technology — Open Systems Interconnection — Abstract Syntax Notation One (ASN.1) — Part 1: Specification of Basic Notation
2. ISO 10303-1:1994 defines in clause "4.3 Information object registration" how to use ASN.1 to identify parts and EXPRESS schemas. Example:
   1. { iso standard 10303 part(41) version(1) object(1) application-context-schema(1) }
3. xxx

APs refer to the ASN.1 in an annex called "Information object registration". For AP214 ed 2 we can e.g. find in clause "E.2 Schema identification":

In the following schema identifications the last item is used to identify the schema name with an ascending number. Number one is used for the expanded listing, number two is used for the short listing, and the numbers three to twentyone are used for the conformance classes one through nineteen.

To provide for unambiguous identification of the automotive_design expanded schema in an open information system, the object identifier

{ iso standard 10303 part(214) version(2) version(1) object(1) automotive-design-schema(1) }

is assigned to the automotive_design expanded schema (see annex A). The meaning of this value is defined in ISO/IEC 8824-1, and is described in ISO 10303-1.

The version number in the ASN.1 identifier is supposed to represent a published version. The DIS is not published so it should not get a version number. The number 0 does not represent the first position in the sequence 0, 1, 2, … It represents the lack of a position in the sequence 1, 2, 3, … So even a DIS for a second edition should have the version attribute set to 0. A version number greater than 0 (position in the sequence) should never be given to a DIS (or a CD).

Since a TC or amendment is published by ISO and modifies the document, the TC or amendment should have a separate version number, even though it is not considered a separate edition under ISO's numbering system. So for AP 203, we should have the following version numbering:

ISO Designation	Version
ISO 10303-203:1994	1
ISO 10303-203:1994/Cor 1:1996	2
ISO 10303-203:1994/Cor 2:1998	3
ISO 10303-203:1994/Amd 1:2000	4
ISO 10303-203:1994/Cor 3:2004	5
ISO/TS 10303-203:2005	6
ISO 10303-203:2009	7