Bernhard Eversberg wrote:
> Am 08.02.2012 12:53, schrieb Karen Coyle:
>> I actually wasn't thinking about readable v. opaque URIs, but that is
>> one topic for best practices. In my experience, you get loud complaints
>> with opaque URIs, but readable URIs are highly problematic.
In ISO TC 46/SC 9 (which develops identifier standards) there is a trend
towards non-semantic (opaque) identifiers. The main argument in favour
of this is that any semantics may eventually become meaningless. A
counterargument is that if the identifier is used as a URI, semantics
may provide a hint for locating the correct resolution service(s) from
the Internet. In this case such hints may not be necessary.
>> I was thinking about things like:
>> - "cool" URIs - hash? or no?
At least some technical experts think that the main weakness of the so
called cool URIs is the need to maintain the domain name registration
(and the organizations' inability to carry on with it for decades). See
>> - PURLs v. agency domains
I would prefer persistent identifiers to cool URIs in this case. But the
PID discussion should not concentrate on PURLs only. There are three
other persistent identifier systems (DOI, Handle and URN) which are more
popular and better standardized.
>> - what should the URI resolve to?
URN-related RFCs are currently being revised (see
http://datatracker.ietf.org/wg/urnbis/). I am currently writing a new
version of RFC 2483, which specifies the resolution services URN can
provide. In the present RFC 2483 the list of services is fixed. RFC
2483bis will be based on the idea that IANA should establish a registry
of informal and formal resolution services. Then URN user communities
could register new services at will (and parameters to these services,
for instance for requesting descriptive metadata about the resource in
Existing persistent identifier systems provide a diverse set of
services. With ARK, for instance, it is possible to check the
preservation commitment of the organisation holding a resource. I don't
know if the PID systems will become more homogeneous in this respect in
Nobody knows what the URIs utilized within this initiative should
resolve to, but I am sure that the mechanism to be built should be
flexible so that it can be adjusted to meet the future needs we don't
>> That kind of thing.
> Does anyone know an answer to any of these questions? Therefore, I
> think, no URI is better than no URI at all. Use brief and simple and
> easily memorized codes for vocabularies like the terms in 337-338, and
> use IDnumbers for names and subjects and titles.
> Any implementation can easily relate them to all sorts of URIs that may
> be in current use or follow best practice or resolve to something
> useful for the purpose at hand. Verbal terms need changes and are
> language-bound, URLs are perishable, only codes and numbers are robust,
> easy to handle, and versatile.
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