W3C home > Mailing lists > Public > public-semweb-lifesci@w3.org > July 2006

Re: [BioRDF] All about the LSID URI/URN

From: Henry S. Thompson <ht@inf.ed.ac.uk>
Date: Tue, 25 Jul 2006 14:35:08 +0100
To: Dan Connolly <connolly@w3.org>
Cc: public-semweb-lifesci@w3.org
Message-ID: <f5bu055g643.fsf@erasmus.inf.ed.ac.uk>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

[HST comments in additional to Dan's]

Dan Connolly writes:

> http://lists.w3.org/Archives/Public/public-semweb-lifesci/2006Jun/0210.html
>
>> The root of the problem is that the URL 
>> contains in it more than just a name. It also contains the network 
>> location where the only copy of the named object can be found (this is the 
>> hostname or ip address) 

Well, either your scheme is intended to be dereferencable, or it
isn't.

 If it is, then instances are likely/virtually certain to contain some
 kind of named starting point, which needs to be looked up and
 resolved to an IP address start the dereferencing process.  Domain
 names and DNS are by far the best available implementation of this
 step, with excellent performance, widespread deployment and
 considerable flexibility.

 If it isn't, it should be!  Dereferencable names are the core of the
 WWW value proposition.

>> as well as the only means by which one may 
>> retrieve it (the protocol, usually http, https or ftp).

Not so.  The URI RFC [1] makes clear that it is up to protocols to
specify what URIs they interpret and how, not the other way around.
It is entirely reasonable, and indeed expected, that new protocols may
specify interpretations of 'old' URI schemes, including 'http'.

>> The first question to ask yourself here is that when you are
>> uniquely naming (in all of space and time!) a file/digital object
>> which will be usefully copied far and wide, does it make sense to
>> include as an integral part of that name the only protocol by which
>> it can ever be accessed and the only place where one can find that
>> copy?

I hope the above clarify that this is not the case for names using the
'http' scheme.  Indeed they are much more likely to do so for 'http'
than for almost any other scheme.

>> Unfortunately when it 
>> comes to URL?s there is no way to know that what is served one day will be 
>> served out the next simply by looking at the URL string. There is no 
>> social convention or technical contract to support the behavior that would 
>> be required.

True for some 'http' URIs, false for others.  The owners of a group of
names, whether they use 'http' or not, are responsible for
documenting, implementing and enforcing usage conventions.  I
absolutely agree that for your purposes you need to take this very
seriously, but using 'http' doesn't make this any harder (or, of
course, any easier).

ht

[1] http://www.gbiv.com/protocols/uri/rfc/rfc3986.html
- -- 
 Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
                     Half-time member of W3C Team
    2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440
            Fax: (44) 131 650-4587, e-mail: ht@inf.ed.ac.uk
                   URL: http://www.ltg.ed.ac.uk/~ht/
[mail really from me _always_ has this .sig -- mail without it is forged spam]
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.2.1 (GNU/Linux)

iD8DBQFExh4MkjnJixAXWBoRAkyqAJ9CuN65g2TWzUiwZyNhOOZnh9x/fQCbB7HT
mML1yZZD+2XCvZtV1l4O/OY=
=Qbp5
-----END PGP SIGNATURE-----
Received on Tuesday, 25 July 2006 13:35:24 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 18:00:44 GMT