Message-Id: <199405181527.IAA19109@rock>
From: Terry Allen <terry@ora.com>
Date: Wed, 18 May 1994 08:27:07 PDT
To: uri@bunyip.com
Subject: URN various
Larry Masinter writes:
| I'm willing to change it to remove 'uniquely' from 'uniquely namable
| entity' if you think it will reduce confusion.
| I'm less willing to remove 'unique' from '... function of a URN is to
| provide a globally unique, persistent identifier', since 'unique'
| modifies 'identifier' and not the resource.
Yes, that's all I want made clear, that URNs are unique in that
no two URNs are (encoded the) same.
| Re: recognition in free text:
| I agree that this requirement is unattainable 100%. I'm willing to
| change it to say:
| > The encoding of a URN should enhance the ability to find and
| > parse URNs in free text.
Yes, that's right.
| since I think that's really what is being desired here. Improve the
| likelihood, by making them say <URN:....>. This is definitely part of
| the ISBN requirements, for example: yah, a publisher could print a
| book with ISBN all over it and things that look like ISBN numbers, but
| it's easy to find the ISBN number on the cover anyway.
I believe that that's not a requirement of the ISBN authority, but a
requirement of book wholesalers (Baker and Taylor has just demanded bar-coded
ISBNs, for example.) I think the parallel is really whether you have
to say ISBN before giving the number; I wouldn't like it to be a requirement
that you say <URN:foo> when foo is a legitimately formed URN.
BTW, is "plain text" defined by MIME?
Dan Connolly writes:
| For the record: I think that the "URN->URL mapping problem" is
| not the right problem. Once you've got a URL, you still have to go get
| the "resource." And you've got security, scalability, and reliability
| issues to deal with there.
I think the discussion has shown that URNs are going to be useful,
but they're a smaller piece of the overall architecture than was
anticipated at first.
| The right problem to attack is "How do we express references, and
| how do we resolve them?" Until I can compose documents that reference
| other documents in such a way that (1) the reference remains meaningful
| despite various inevitable changes in the world, (2) my reader
| can follow the references reliably, we have made no progress.
I think even (1) is a worthy goal. I'd invert point 2: my reader
will not get the wrong source when he follows a reference, although
he may get nothing at all.
One item from the minutes has been bothering me a bit:
| o URNs must be built with a limited character set in order to be
| transportable
This seems like a short-term desideratum compared with the eternal
life of URNs. All is okay for now, but eventually won't there be a
way to use any character one desires in a URN?
Regards,
-- Terry Allen (terry@ora.com) Editor, Digital Media Group O'Reilly & Associates, Inc. Sebastopol, Calif., 95472