Message-Id: <9404260314.AA08081@expresso.bunyip.com>
From: Peter Deutsch <peterd@bunyip.com>
Date: Mon, 25 Apr 1994 23:14:44 -0400
In-Reply-To: Dirk Herr-Hoyman's message as of Apr 22, 12:59
To: hoymand@gate.net (Dirk Herr-Hoyman), Terry Allen <terry@ora.com>
Subject: Re: Yet more URI/URC
[ You wrote: ]
> >I think the bug is that I can give a URN to something of yours
> >that you've already given a URN to. I doubt this happens today
> >with ISBNs except rarely, but it could be a problem on the net.
But if you and I both have either our own naming
authorities, or a distributed portion of a single naming
authority, then I don't see that this is a bug at all. If
you are a trustworthy server of URNs, and I'm not, that
too will factor into which of us people choose to use but
there can't be any confusion as to who's assigning URNs
here, or did I miss something?
> And just like with MARC or other library catalog records.
I don't think URNs map to MARC records, but rather ISBNs.
O'Reilly can't issue the same ISBN to more than one of its
titles, but Wiley can certainly issue a similar identifier
string to one of its texts. The trick is that the portion
of the ISBN that identifies publisher will allow us to
tell the two apart.
> This could be handled by some type of signature on the resource itself.
> Just like a book has the ISBN number in it, a resource would have the
> "authorized" URN. Even in plain text, but I suppose there could be a
> digital signature involved. . . .
Actually, the same book _can_ have multiple ISBNs and I
believe that varous network resources will potentiall have
multiple URNs. One example of this is in the publishing
world occurs when the same book is published in different
countries by different publishers (people show up at the
Frankfurt Book Fare in October each year and negotiate
rights to any one of thousands of titles for any one of
hundreds of countries. It's a _huge_ business).
Now, as long we we can distinguish among the different
publishers (either by using differing naming authorities,
or better by using a distributed naming authority for
multiple publishers) there should be no confusion. I may
even choose to offer a value-added service offering
"customized" URNs. There are companies now that make their
living taking cataloging info from the publishers and
offering a single master catalogue (Book Data is one).
It's only a small step to assigning your own URNs to these
and one that some people may take to ensure quality of
their offerings.
> . . . While this doesn't fit into the URN lookup
> servers that we are discussing (since you couldn't trust them), for
> something like HTML resources and clients it would work.
Actually, I'm not sure that it doesn't. I assume that most
naming authorities will have their own resolution servers
(although of course, some will not. Remember that
resolution is desireable, but not always possible and we'd
better allow for that in our design).
> But, I see your point and I don't see how one can prevent "bogus" URN
> servers from springing up, short of cutting 'em off at the knees by
> preventing their INITIAL lookup. Does this imply Network URN police (sigh
> :-()?
I don't see that this will be needed. The purpose of the
naming authority portion of the URN that we proposed was to
permit control over who gets to perform the conversion on
that naming authority's behalf. I'd originally thought of
using the IANA to maintain a registry of naming
authorities but I now agree that using DNS (which also has
a mechanism for guaranteeing authority and it has the
advantage of being distributed) makes more sense. Once we
have that in place, than distinguishing between:
urn:myname.urn.int:war-and-peace
urn:yourname.urn.int:war-and-peace
is easy. The first gets resolved by "myname.urn.int" and
the second by "yourname.urn.int" (and apologies if I have
the syntax on this wacko. I'm not proposing an
alternative, I just don't have the details handy).
- peterd
--
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"What do thay got, a whole lot of sand? We got a hot crustacean band!
Each little clam here, know how to jam here! Under the Sea!"
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