Re: URN UUID question

Joel Kalvesmaki <> Tue, 11 March 2014 19:31 UTC

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Date: Tue, 11 Mar 2014 15:31:11 -0400
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Subject: Re: URN UUID question
From: Joel Kalvesmaki <>
To: Peter Saint-Andre <>
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Thanks for the suggestion. I had considered that option, but the string
must conform to XML schema's <anyURI>,[1] to suit the purposes I mentioned
(RDF, etc.). And no <anyURI> may begin with a numeral. It would also be
important to have a scheme that any human or computer would recognize
immediately as a URN.

I had also considered the following (where NN = a suitable project-specific
abbreviation or dt = date-time, as a project-agnostic urn scheme):


But would either one require registration with IANA? If so, what what's the
process and is it worthwhile? I have heard of at least one project that has
simply coined its own urn:NNN: scheme on its own, but I do not fully
understand what consequences face anyone setting out on that direction.

One other possibility occurs to me, that of treating the time-date stamp as
a fragment identifier:

But I suspect that would violate the RFC 4122 definition, no?

Best wishes,



On Tue, Mar 11, 2014 at 1:24 PM, Peter Saint-Andre <>wrote;wrote:

> On 3/4/14, 8:32 AM, Joel Kalvesmaki wrote:
>> I am developing an XML data model that requires users to name versions
>> of a document. Each version's name should be unique, but patterned to
>> allow anyone (human or computer) to associate it with the names of other
>> versions of that document and to place it in chronological sequence. The
>> name of each version must be a single string, specifically a IRI/URI (to
>> facilitate, among other things, straightforward declarations in RDF). It
>> should not be split into two elements. Naming must be as decentralized
>> as possible.
>> My favored scheme for naming these entities would concatenate a UUID
>> (any style), a middle delimiter, and an ISO date/dateTime, e.g.,
>> urn:uuid:f60330fd-1900-44ac-a825-de70074e142e::2014-02-07Z
>> urn:uuid:f60330fd-1900-44ac-a825-de70074e142e::2014-02-28T00:20:58.3Z
>> Would it be misleading to begin such a string with "urn:uuid:" and if
>> so, what are the alternative best practices?
>> Perhaps there already exists a urn scheme that does what I intend?
>> Are there any other issues I should consider before adopting a naming
>> scheme like this?
> As far as I can see, you don't really need or necessarily want the
> "urn:uuid:" string at the front. Why not things like this?
> f60330fd-1900-44ac-a825-de70074e142e::2014-02-07Z
> f60330fd-1900-44ac-a825-de70074e142e::2014-02-28T00:20:58.3Z
> Peter

Joel Kalvesmaki