[Nml-wg] Identifier Proposal

[Freek Dijkstra]

Jeroen van der Ham wrote:

> In the end in the meeting there 
> was consensus on using the following:
> 
> 	urn:ogf:network:<dns name>:<opaque part>
> 
> If you have any questions or comments on this proposal, please let us know.

The use of URNs comes with some requirements, as defined in these RFCs
(in order of importance):
http://tools.ietf.org/html/rfc3986 - URI: Generic Syntax
http://tools.ietf.org/html/rfc2141 - URN: Generic Syntax
http://tools.ietf.org/html/rfc2611 - Clarifications and Recommendations
http://tools.ietf.org/html/rfc3305 - URN Namespace Definition Mechanisms

For example, any URN "is required to remain globally unique and
persistent even when the resource ceases to exist or becomes
unavailable" (rfc3986). So identifiers may never be re-used, period.

* Is there a maximum length for a name?
* What normalization is required for lexical equivalence?
  (just UTF-8, no BOM, NFC? lower case/upper case?)
* what are allowed characters (may the opaque part contain ":" or
  the NULL character? Or Line Feed?)
* whose dns name is used? From the source domain, or from whoever
  generates the identifier? In particular, what if domain A does not
  (yet) generate global identifiers, but domain B has a link terminating
  in that domain. May domain B just generate some sort of identifier
  just to be able to refer to it?

I think most of the answers are in the RFCs, but it is good to be
explicit, especially about the normalization, as that is mostly left
open for users of a URN.

I'm willing to work with Lars, who has volunteered to write the section
on identifiers.

Regards,
Freek Dijkstra