Version Numbering Scheme
As 3GPP Technical Specifications and Technical Reports evolve from the early drafting stages, though progressively more stable versions, to being brought under change control, so the version number of the document changes. The rules for maintaining the version number are contained in clause 4.4 of 3GPP TR 21.900, but are briefly summarized here.
The "version" is comprised of three fields:
- major
- technical
- editorial
Each field has a numeric value, starting with zero. The fields are separated with dots, and the version number shows major, technical and editorial fields respectively from left to right. Thus a spec whose major field is 4, whose technical field is 7 and whose editorial field is 1 would be shown as version 4.7.1.
Major version field
The major version field reflects the stage of the spec:
- 0 = immature draft
- 1 = draft which is at least 60% complete and has been presented / will shortly be presented to the responsible TSG for information
- 2 = draft which is at least 80% complete and has been presented / will shortly be presented to the responsible TSG for approval
- 3 or greater = spec which has been approved by the responsible TSG and is under change control.
Technical version field
Once under change control, the major field indicates the Release to which the spec applies. Thus it is quite normal for a Release 7 specification to go, on TSG approval, from version 2.0.0 directly to version 7.0.0. There will be no versions 3.0.0, 4.0.0 etc between.
The technical version field is incremented each time a technical change is made to the spec as a result of the drafting process (major version <= 2) or as a result of the incorporation of one or more approved Change Requests (major version > 2).
Editorial version field
The editorial version field is incremented each time a non-technical change is made to the spec, for example to correct trivial typographical errors.
Note that any change which could conceivably have an effect on the interpretation of the technical provisions of a spec cannot be considered as editorial. (example: Changing the greater-than symbol > into the less-than symbol <, although only the result of a mistyped character, is not considered editorial, since it makes a profound difference to the interpretation of the technical provisions of the document.)
Exceptionally, the editorial version is used to show the replacement of a new version of a spec within the period (normally three working weeks) immediately following the end of a TSG meeting prior to the "all specs available" deadline, even though the modification might be more than purely editorial. Such circumstances cover, for example, the late availability of C code or TTCN associated with a spec.
The document’s change history annex will always explain the nature of any such change.