[Nml-wg] Interface vs Port

[Jeroen van der Ham]

Hello,

On 30 Aug 2011, at 03:20, Jason Zurawski wrote:

> Hi Jeroen;
> 
> On 8/26/11 7:47 AM, thus spake Jeroen van der Ham:
>> Hello,
>> 
>> A long time ago we have had a discussion on naming, where we
>> finalized on Nodes and Ports. However, due to feedback that I'm
>> getting in projects where semantic network descriptions are now
>> actually being used, I have received requests to change Port to
>> Interface.
> 
> Which projects, and when have you interacted with them or when have they 
> approached you about this topic?  You note 'requests' so please be 
> specific if you could.

The projects in question are:
- GEYSERS: EU project that we are also involved in, see http://geysers.eu
- NOVI: EU project that we are involved in, see http://fp7-novi.eu
- NDL-OWL: RENCI created an extension to NDL for the GENI context and has used also Interface there.
- PlanetLab: also uses Node and Interface in their RSpec files.

>> The problem is that in these projects the network descriptions become
>> part of a larger infrastructure.
> 
> One could say that about just about any project looking to adopt the NML 
> work, I don't believe these new groups are much different than anyone 
> else in that regard.

True. Traditionally our application area has been SURFnet, NetherLight and GLIF, which are very network-centric. For us it is a recent development that we look beyond the network and start applying semantic descriptions there.

>> Having an object named Port there to
>> describe a network connection point is confusing to users who are not
>> network-centric. They think that a Port object would describe
>> something like a TCP/UDP port, instead of a whole network interface.
> 
> This sounds like a similar argument I can remember from 2007, when the 
> founders of NML first got together to try to combine concepts from 
> NDL/NM into something cohesive.  My hazy memory seems to remember 
> 'interface' and 'port' being on the table.  At the time the group went 
> with one ('port') since it was silly to endlessly debate on something 
> like a name when there were other important things to deal with.

That's similar to how I remember it. It seems that now we do have an argument for Interface.

> 
>> Would it be possible that NML also changes the Port object to
>> Interface, so as to sync up with the schemas that are already in use
>> in GENI, Geysers and NOVI?
> 
> You note a key problem in this request - "A long time ago we have had a 
> discussion on naming".  Lots of water has flowed under the bridge since 
> that date, and products/software have latched on to these concepts over 
> the span of years.
> 
> Speaking selfishly only for things I care about (e.g. perfSONAR products 
> and control frameworks such as OSCARS that have adopted 'in progress' 
> versions of NML), I am not pleased to hear about this particular request 
> given the amount of investment that has been made.  Lots of interactions 
> (protocol based and internal software management) have been structured 
> around these concepts, and these products are deeply embedded and 
> deployed in the infrastructure of many networks.  I don't believe that 
> this amount of investment should be forgotten as the group considers 
> something as simple as a 'find/replace' in current documents.
> 
> I personally would like to know more about these projects, and the 
> reasons why they are approaching this working group (and by extension 
> projects that have already started to implement NML concepts as is) with 
> a request to go through a lot of work to re-introduce an old argument. 
> I am all for collaboration, but it is not clear to me what benefits NML 
> will receive as a tradeoff with these other projects.

The projects have used NML (and other ontologies) as a basis for semantic representations. We are involved in both GEYSERS and NOVI. We've used the Port object, and others in the project have requested that we use the Interface object.
Other projects have already used the Node/Interface pair.

To me personally it does not seem like a very strong argument that we should not change anything in NML, because people have started using it. NML is not finished yet, while we're in the final stages, there is still a possibility of change. To me, implementers take a risk in adopting NML.

It seems though that more and more projects are going for "implementations" of NML, so perhaps we should start considering a "code freeze" soon.

Jeroen.