[Nml-wg] About modelisation of the network description

[Aurélien Cedeyn]

Le mardi 04 mars 2008, Evangelos Chaniotakis a écrit :
> Aurélien Cedeyn wrote:
> > Le samedi 01 mars 2008, Freek Dijkstra a écrit :
> >> Aurélien Cedeyn wrote:
> >>> I send you a little document that i made which describes a new object
> >>> in the NML : the model object. All the description and motivation about
> >>> this addon are in the attached document.
> >>
> >> Aurélien, thank you so much! Very good write down! These are the
> >> contributions that will help the NML workgroup a lot.
> >
> > Hi Freek,
> > What an impressive mail :)
> > I'll try to answer shortly but clearly to your questions.
> >
> >> I wholeheartedly agree with what you write, although I use different
> >> terms, and I don't understand all details of what your propose yet.
> >> Allow me to ask a bit, so I'll understand.
> >>
> >>> The NML goal is to instance modelisations of the real topology. This
> >>> real topology is too complex regarding the description needs of
> >>> applications, some informations are not needed.
> >>
> >> True, and true. But I think that modelling of the real topology is only
> >> ONE OF the goals of NML. What you write is that you also like to see NML
> >> capable of describing "modelisations" of the real topology (I would call
> >> it abstractions of the real topology). I wholeheartedly agree that that
> >> should also be another goal of NML.
> >>
> >> First a rather academic remark: what exactly is a "real topology" and a
> >> "modelisation" or "abstracted" topology? Most network engineers, even
> >> when asked for the "real topology" will describe fibers and devices, but
> >> still abstract a lot: they often leave out patch panels, and the
> >> internal workings of devices itself: because they either find it
> >> irrelevant (decribing patch panels is only relevant if you care about
> >> inventory management, or power loss details) or because they simply
> >> don't know the information (few people know how exactly devices work on
> >> the component level). In short: nearly everything is already a
> >> "modelisation", although the level of abstraction greatly differs
> >> between each model, and it is there where the discussion starts.
> >
> > Exactly, that's what i mean with "Modelisations". The question is : "Does
> > NML have to provide the extrem details of a real network such as patch
> > panel ?"
>
> Can we call them "Views" instead of "Models"? "Model" is a quite overloaded
> word, especially in a semantic context.
>

I tortured myself to find the good word to represent what i mean. First i used 
the term of "View" but view implies that a description is already here. 
The model concept is not only a view, it is a network modelisation itself 
which can be connected with others model.

> But otherwise, thanks for writing this up. This is really close to work
> currently
> under development in the IDC project.


regards,

-- 
Aurélien Cedeyn                   Comité Technique Grid'5000 Lyon
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