Internet Info 1997 December/Internet_Info_CD-ROM_Walnut_Creek_December_1997.iso/ietf/urn/urn-archives/urn-ietf.archive.9701/000008_owner-urn-ietf _Mon Jan 13 12:55:39 1997.msg

Internet Message Format | 1997-02-19 | 4KB

Received: (from daemon@localhost) by services.bunyip.com (8.6.10/8.6.9) id MAA06583 for urn-ietf-out; Mon, 13 Jan 1997 12:55:39 -0500
Received: from mocha.bunyip.com (mocha.Bunyip.Com [192.197.208.1]) by services.bunyip.com (8.6.10/8.6.9) with SMTP id MAA06578 for <[e-mail]>; Mon, 13 Jan 1997 12:55:36 -0500
Received: from josef.ifi.unizh.ch by mocha.bunyip.com with SMTP (5.65a/IDA-1.4.2b/CC-Guru-2b)
        id AA00951  (mail destined for [e-mail]); Mon, 13 Jan 97 12:55:30 -0500
Received: from enoshima.ifi.unizh.ch by josef.ifi.unizh.ch with SMTP (PP)
          id <[e-mail]>; Mon, 13 Jan 1997 18:54:59 +0100
Date: Mon, 13 Jan 1997 18:54:58 +0100 (MET)
From: "Martin J. Duerst" <[e-mail]>
To: Ryan Moats <[e-mail]>
Cc: [e-mail]
Subject: Re: [URN] [Fwd: Proposed URN Syntax Draft changes to align with URL
         syntax draft]
In-Reply-To: <[e-mail]>
Message-Id: <Pine.SUN.3.95.970113184100.245U-100000@enoshima>
Mime-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
Sender: [e-mail]
Precedence: bulk
Reply-To: "Martin J. Duerst" <[e-mail]>
Errors-To: [e-mail]

On Thu, 9 Jan 1997, Ryan Moats wrote [regrouped]:

> Well, here we are in the week of 1/6/97 and some issues have come up
> vis-a-vie the URL syntax document.  Here are the technical issues (as I
> see them, and I've probably missed/ignored some):
>
> 1. The URN syntax is more restrictive in the types of characters
> allowed vis-a-vie the URL syntax.  Specifically, the characters
> ";", "$", "_", "!", "~", "*", "'" are allowed (in unescaped format)
> in the URL syntax while not in the URN syntax.

> My current thoughts are to move the characters in note 1 above from the
> excluded character set to the allowed character set to more closely
> align the URN and URL character sets.  IF SOMEONE THINKS THIS IS A BAD
> IDEA THIS IS A GOOD TIME TO LET ME KNOW!

With exception of "~", for which some change has been going on in
the URL syntax draft, they should be in. The reasoning for this is
that we don't know what kind of reserved characters a namespace would
like to use, but we know that it can only use those that we include.


> 2. The URL syntax document makes a claim that the its syntax is the
> syntax for URIs in general so that URNs may be used in any data field
> that might otherwise hold a URL.
>
> I'll admit that there are a lot of political issues that I am ignoring
> for now, but I want to see if we can move forward with the technical
> issues.

> Issue 2 is handled (I believe) by adding an appendix to the URN syntax
> document that covers how a URL resolver should react to a URN. My
> proposal is that the URN be considered an opaque URL that gets handed
> off to a URN resolver. There are alternate solutions, but they become
> progressively more ugly.

Yes, this is a good way to describe it. Please make sure you don't
write "an URL resolver SHOULD", but that you describe this as a possible
way to proceed that clarifies the relationship between URLs and URNs.



> Note that issues 1 and 2 are somewhat independent.  Given the current
> allowed characters and the above suggested appendix, any URN could be
> used in place of a URL.
>
> Although I've considered it in the past, I think that defining URN's as
> a URL "scheme" is a less optimal solution than the above proposals.

I agree we should not say that an URN is an URL "scheme".
Syntactically, it is equivalent to an URL scheme, but semantically,
it is something different.


Regards,    Martin.