[Nml-wg] Simple example #1

[Roman Łapacz]

W dniu 2012-07-11 15:47, Freek Dijkstra pisze:
> On 11-07-2012 15:38, Roman Łapacz wrote:
>> W dniu 2012-07-11 15:26, Freek Dijkstra pisze:
>>> On 11-07-2012 15:16, Roman Łapacz wrote:
>>>>       <!-- COMMENT
>>>> !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
>>>> -->
>>>>       <!-- I propose to use new Relation="representedBy"  -->
>>>>       <!--- when an object (in this case a Link can be represented by
>>>> an other. Definition of them is the same! -->
>>>>
>>>>       <nml:BidirectionalLink
>>>> id="urn:ogf:network:domainy.net:2012:domainx-domainy-domainx">
>>>>         <nml:Relation
>>>> type"http://schemas.ogf.org/nml/2012/07/relation/representedBy">
>>>>           <nml:Link
>>>> id="urn:ogf:network:domainx.net:2012:domainx-domainy-domainx">
>>>>         <nml:Relation>
>>>>       </nml:Link>
>>> I'm not (yet) sure what you mean with this definition. Can you elaborate
>>> a bit?
>>>
>>> My first thought was that you meant an identity relation, like
>>> 'isAlias', but since these are two different objects, I guess it's
>>> something different. To me, a BidirectionalLink is just a grouping of
>>> two Links, with the (implicit) "hasLink" relation.
>>>
>>> Perhaps a short example in words my help me understand.
>> The question is which domain name should be included in the URN of an
>> inter-domain link. In this case domain x or domain y. One could say that
>> one of those two (that's fine and I remember a discussion about this
>> problem in the OGF meeting). But we could also create two bidirectional
>> links and one of them is just an an alias (the best name but I wasn't
>> sure if I can use it as I'm not 100% sure of the definition of isAlias
>> used in the NSI example).
> Ah, sorry I got confused because in the XML your relation was
>
> BidirectionalLink --(representedBy)-->  Link
> instead of
> BidirectionalLink --(representedBy)-->  BidirectionalLink
>
> It is now clear to me. I indeed think this is the same as an 'isAlias'
> relation. I don't have a solid definition at hand, but indeed it should
> be some sort of identity relation, which can be used for two different
> purposes:
>
> * The above: joining two identifiers given out by different
> organisations if they -for whatever reason- can not agree on a common
> identifier.
>
> * To add a level of indirection so that a more abstract identifier can
> be used externally while a more concrete identifier is used internally.
> E.g. the abstract "link-domainx-domainy" isAlias of the concrete
> "link-domainx-device-Ahc34-intf3.1-to-domainy-device-Bfg5-intf0.28"
>
> I'm not sure if we should use the "isAlias" relation for both purposes,
> but for now I don't see why not.

Let's keep this isAlias definition issue in mind and discuss it with 
Jeroen and others during next call (I want to be sure that my 
understanding of it is not different from how it was used for the NSI 
example).

Roman

>
> Freek
>
> (PS: Sorry that my mail client is also messing up the example with it's
> wrapping. I recently moved back to Thunderbird, and came to the
> conclusion that all mail clients still suck. Offlist suggestions are
> appreciated.)