Subject: [mile] draft-montville-mile-enum-reference-format-00.txt - spec versions

From: "Black, David" <[email-masked]>
Date: Mon, 5 Nov 2012 16:44:34 -0500

Hi Adam,

I concur with Take's concern that different versions of the same
specification may or may not be able to share an enumeration format,
and hence may or may not be able to share a registered id_type.  We
could leave this decision about id_type sharing among spec version to
the Designated Expert with suitable guidance about compatibility among
versions that share an id_type.  One baseline rule to start with is
that any change to the id format that could cause a parser for the old
format to not correctly parse an id in the new format MUST use a
different id_type string (for example, suppose that CXI versions
1.0, 1.1, 1.2 and 1.2.1 use the same id format, but a completely new
and incompatible id format was introduced in CXI version 2.0 - we might
have registry entries for CXI and CXI2).

For each id_type, the registry could list the spec versions that use
that id_type.  This could get verbose if every version includes a name,
link and citable reference in the registry, so perhaps the registry
could contain full details for only the latest version (including its
version number), plus a list of other versions that use the same format.

Does that sound reasonable?  Are the specifications for these enumerations
revised often enough that a list of spec versions for each id_type helps?

In addition, I suspect (unfortunately) that something will need to be
said about Unicode characters in id (and id_type).  I'll defer to others
(e.g., Take) as to whether we can get away with an ASCII-only restriction,
although I'm skeptical that ASCII will suffice. OTOH, Kathleen's already
pointed out that the Unicode considerations in RFC 5070 (IODEF) need
work, so perhaps some of what's needed for Unicode considerations can
be left to the effort to revise RFC 5070.

Thanks,
--David
----------------------------------------------------
David L. Black, Distinguished Engineer
EMC Corporation, 176 South St., Hopkinton, MA  01748
+1 (508) 293-7953             FAX: +1 (508) 293-7786
[email-masked]        Mobile: +1 (978) 394-7754
----------------------------------------------------