Globally Unique Identifier

Gregor Hagedorn G.Hagedorn at BBA.DE
Wed Sep 8 18:20:19 CEST 2004

I am not quite sure, but to me it seems with "GUID" you refer to the
numeric, MAC-address generated GUID type. I have nothing against
these. However, any URN in my view is a GUID that has most of the
properties you mention:

> - it is guaranteed to be unique globally, and can be created anywhere,
> anytime by any server or client machine - it has no meaning as to
> where the data is physically located and will there not confuse any
> user about this

> - most id
> mechanisms, especially URI/URN ids require a 'governing body' to
> handle namespaces/urls to ensure every URN is unique, whereas a GUID
> is always unique

The governing body is restricted to the primary web address, and in
most cases such an address is already available. Being a member of a
governmental institution that explicitly forbids the use without
prior consent, and forbids the use of its domain name once you are no
longer working for them, I realize some potential for problem.

> I do think a URL of some kind would be useful for things such as
> global searches of multiple databases, as this will allow the search
> to go directly to the data source where the name, referene, etc comes
> from.  But this should not be part of its ID.  Maybe a name/id should
> have several foms, a GUID for an ID and a URL + a GUID for a fully
> specified name.
> What are the current thoughts on these ideas?

A GUID is only part of the problem. The other half of the problem is
actually getting at the resource. URN schemes like DOI or LSID (I
prefer the latter) intend to define resolution mechanisms. That make
the URN not yet a URL - in my view the good comes with the good,
location and reorganization independence.

I believe GBIF should install such an LSID resolver, which is why in
the UBIF proxy model, under Links, I propose to support a general URL
(including potentially URNS), a typed LSID and a typed DOI. This
could be simplified to have just a URN (LSID and DOI are URNs), but
that would then require string parsing to determine and recognize the
preferred resolvable GUID types. Comments on splitting/not splitting
this are welcome!

There may be some need to define a non-resolvable URN/numeric GUID as
well. However, that would not be under the linking question. Is it
correct that linking requires resolvability, or am I thinking into a
wrong direction?


Gregor Hagedorn (G.Hagedorn at
Institute for Plant Virology, Microbiology, and Biosafety
Federal Research Center for Agriculture and Forestry (BBA)
Koenigin-Luise-Str. 19          Tel: +49-30-8304-2220
14195 Berlin, Germany           Fax: +49-30-8304-2203

Often wrong but never in doubt!

More information about the tdwg-content mailing list