Subject: Re: [apps-discuss] [uri-review] tn3270 URIs

From: Alfred Hönes <[email-masked]>
Date: Fri, 19 Nov 2010 15:06:14 +0100 (MEZ)

Tom, all,

Tom Petch wrote:

>   [...]   I would even offer to review an updated specification
> (although I think that that would be overkill).

I'm fine with a specification if the 'tn3270' scheme actually is
in use and new implementations (of the scheme) might be expected
as well, but I could not find an old spec that could be "updated".
So please provide a virgin registration document per RFC 4395,
if you are interested.

What I'm opposing to is letting a "provisional" registration linger
around in the registry for decades / forever.
"Provisional" is intended as a transient state, but it also requires
a registration per RFC 4395.  'tn3270' never got that so far.

RFC 1738 said (sect. 4, pg 17):

|  The following scheme have been proposed at various times, but this
|  document does not define their syntax or use at this time. It is
|  suggested that IANA reserve their scheme names for future definition:
|
|  afs              Andrew File System global file names.
|  mid              Message identifiers for electronic mail.
|  cid              Content identifiers for MIME body parts.
|  nfs              Network File System (NFS) file names.
|  tn3270           Interactive 3270 emulation sessions.
|  mailserver       Access to data available from mail servers.
|  z39.50           Access to ANSI Z39.50 services.

That's all what it says about 'tn3270'; no single additional word.
Notably, it uses verbiage like "have been proposed"  and
"reserve ... names for future definition".

Three entries from that list are still pending -- 'mid' and 'cid'
(per RFC 2392) and 'nfs' (per RFC 2224) have been formally specified,
'z39.50' has been obsoleted and replaced by 2 schemes (per RFC 2056).

Alexey's draft retires 'mailserver'.

For 'afs', it looks like support for declaring it Historic is emerging.

If there's no spec for 'tn3270' by the end of next year, I'll revisit
the topic of declaring this scheme Historic.

Note that even arguably "dead" schemes like 'wais' and 'prospero'
have at least been formally specified before they have been declared
Historic (RFCs 4156 + 4157).

RFC 4395 requires for the registration of Provisional URI schemes:

   [...]
   o  Contact information identifying the person supplying the
      registration is included.  Previously unregistered URI schemes
      discovered in use may be registered by third parties on behalf of
      those who created the URI scheme; in this case, both the
      registering party and the scheme creator SHOULD be identified.
   o  If no permanent, citable specification for the URI scheme
      definition is included, credible reasons for not providing it
      should be given.
   o  A valid Security Considerations section, as required by Section 6
      of [3].
   o  If the scheme definition does not meet the guidelines laid out in
      Section 2, the differences and reasons SHOULD be noted.

The RFC and historic I-D repositories apparently do not contain
any document that could be taken as qualifying for such registry
entry for 'tn3270' under these provisions.

Kind regards,
  Alfred Hönes.

-- 

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