Registration of a MIME type for ABC

The draft was transmitted to the ABC developers list on 1997 August 18, and suggestions from the developers were incorporated. The draft was transmitted to the ABC users list on August 25, and polishing of the text continued. It was submitted as a request to the IANA and the IETF-types mailing list on September 8. The IANA registered it on 1997 September 11 and placed it on the IANA anonymous FTP site.

This places ABC in the view of the entire internet community.

Among the advantages of MIME registration is the likelihood that it will trigger the development of Web Browser Plug-Ins which can process ABC files.

This commentary will remain at this URL until I reorganize my WWW hierarchy. My thanks to everyone who contributed to the editing process.

Explanatory commentary on the ABC MIME type

The request follows the template given in RFC 2048, and incorporates relevant wisdom from all parts of the MIME RFCs (2045 thru 2049). See, e.g., http://info.internet.isi.edu/in-notes/rfc/files/rfc2048.txt.
MIME media type name: text
ABC is human-readable, therefore its MIME type should be "text".
MIME subtype name: vnd.abc
vnd.* is the namespace tree reserved for "vendor" or "producer" MIME subtypes. If Microsoft were to produce yet another new app with files which were expected to be widely used then its MIME subtype would be something like "vnd.microsoft.newapp". It is not required that vendor mime types provide any syntax specification, but to its great credit ABC has one.

The other option besides vnd.* would be the prs.* tree for "personal" MIME types. With some 10000 tunes on the WWW, and more than a dozen different apps for interpreting it, ABC deserves to be in the vendor tree. The fact that there is no actual corporation producing ABC is not relevant, there are other examples of "vnd.*" types which are defined by a pair of individuals.

The MIME spec may be interpreted as requiring a subtype such as vnd.corporate_name.product_name but as ABC is a single product I believe that the extra level of hierarchy can be omitted. The IANA concurred.

Required parameters: [none]
Optional parameters: version, charset
charset is described below under encoding.

version means that the MIME type as supplied by a WWW server might be
text/vnd.abc; version=1.6
to indicate conformance with Chris Walshaw's 1.6 specification. The version may consist of any ASCII letters or digits.

Version numbering is a can of worms which implies a central registry for publishing syntax variations of different ABC applications. In the best of all worlds we will never make use of it, but it is added here to permit its use should we find it necessary.

Encoding considerations:
In most cases a single abc file will use a single character set. For those cases the abc files could employ a magic number convention derived from the generic text MIME types. Namely, that the first line of a current abc file which uses standard ASCII begin with
%abc
A hypothetical abc version 2.0 file which uses some Cyrillic characters might simply begin with something like
%abc-2.0 charset=ISO-8859-5
(where ISO-8859-5 is a standard Latin/Cyrillic character set)
Security considerations:
Interoperability considerations:
Published specification:
There is sufficient redundancy in these URLs to remove concerns about the permanance of any one. The MIME type can be updated should it become necessary.
Applications which use this media type:
Additional information:
Magic number(s): "%abc"
The format of a version-qualified first line would be
%abc-1.6
where the version follows the "-".
The caveat about version discussed above also apply here. Unless a central registry of versions is created the developers discourage the use of version information.
File extension(s): ".abc"
Macintosh File Type Code(s): TEXT
It was pointed out that the Mac Creator type cannot be made specific because there is more than one ABC app for Macs.
Person & email address to contact for further information:
This list should prove complete enough for the purposes of the registration. I might have liked to have included all the ABC developers, but obtaining permission would have proved infeasible.
Intended usage: COMMON
Other options are "LIMITED USE" and "OBSOLETE". With 10000 ABC files online ABC qualifies as common.
Author/Change controller:
I have placed my reputation before the IANA here; thus taking responsiblity should any updates to the MIME type be required. The IANA has marked me as the point of contact. Reassignment of the owner is possible should it become necessary.
After the official template of the registration proposal may go any other information that might be deemed interesting. I believe that the final 4 paragraphs are an adequate description.

Where does ABC as MIME go from here?

I hope that ABC continues to evolve and grow in popularity. If it reaches the stage of the mythical abc-2.0 which handles most everything everyone wants, and if its popularity continues to grow, then it is worth considering applying for a top level MIME type. Such a type might be "text/abcmusic", and it would require that a full-blown RFC be written. This is a goal we should keep in mind.
Steve Allen <sla@ucolick.org>