[Nml-wg] Deviating from GFD.84

[Richard Hughes-Jones]

Dear Freek

I have now been able to have a look at GFD.84; so some comments on your proposal:

1. I like the idea of having the same URI for both the XML and RDF namespaces. 
2. Although "/nml/2012/10/base" might not be fully in line with the GFD.84  "project version project" but it is in agreement with GFD.84  "project version part" and I think "base" is more informative than repeating "nml".
3. Your suggestion to make the common URI point at a web page with either two sections or two pointers to cover both the XML and RDF is a good approach.
4. re "#" or "/" using "#" follows best practice to end an RDF namespace, so use that.

I hope this helps

Regards
Richard Hughes-Jones
Senior Network Advisor
The Office of the CTO


-----Original Message-----
From: Freek Dijkstra [mailto:Freek.Dijkstra at sara.nl] 
Sent: 08 August 2012 10:31
To: Richard Hughes-Jones
Cc: Ali Anjomshoaa; Michel Drescher; Network Markup Language Working Group
Subject: Deviating from GFD.84

Hello Richard, I'm writing to you as OGF Area Director, cc authors of GFD.84,

The NML working group is defining a UML schema for network topology descriptions with a syntax in both XML and RDF/OWL.

We like to use the same URI for both the XML and RDF namespaces, but found that XML and RDF use namespaces in a different way. To make the NML namespace valid for both RDF and XML, we like to deviate from GFD.84, which defines the syntax of OGF namespaces.

In particular, we are thinking of ending the namespace with a hash (#) or slash (/), as required by RDF.

Secondly, we are considering using "base" for the part name of the base schema, instead of repeating the project name.

So instead of using
   http://schemas.ogf.org/nml/2012/10/nml
   http://schemas.ogf.org/nml/2012/10/ethernet

We like to use either:
   http://schemas.ogf.org/nml/2012/10/base#
   http://schemas.ogf.org/nml/2012/10/ethernet#

or
   http://schemas.ogf.org/nml/2012/10/base/
   http://schemas.ogf.org/nml/2012/10/ethernet/

Do you have any objections to these namespaces, and do you have any advise on the choice for hash or slash variant?


Note that it is not possible to publish both the XML and RDF/OWL schema at the specified URI, but we plan to put a HTML document at the specified URI with (RDDL and human readable) pointers to both schemata.


FYI, these are the most important differences between XML and RDF
namespaces:

- Namespaces in XML are used for scoping, in XML the element name
  and namespace are separate parts in identifying a single thing.
- Namespaces in RDF are used like prefixing, the element name and
  namespace are concatenated to form a single identifying URI.
- It is *best practice* to not end XML namespaces in "/" or "#",
  but it is perfectly valid to do so, and many standards do.
- It is *best practice* to end an RDF namespace in "#", but it is
  perfectly valid to use something else, some standards also use "/".

Regards,
Freek Dijkstra