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NIM: What we want to accomplish



I agree with Randy (because he has his reality hat on) and vote for inherent
simplicity, methods notwithstanding. Fundamentally, we want a model that is
easy to grok and is attractive to the subject experts such that THEY can
move relevant information out of their heads and into the model. This is
verses having modeling experts have to learn what's in all the subject
matter experts heads and try to integrate this into a model.

To me this means:

1. Avoid excessive hierarchy
2. Avoid class REFERENCE explosion (Perhaps by avoiding aggregations and
instead using good-o'l-fashion containment and by creating some short-hand
notation for the real associations)
3. Reusability of ALL constructs (existing and future). Model it once
(extend it many), so that we don't keep re-inventing the wheel.
4. Scope the model... People tend to only be interested in a particular
subject area, so have mechanisms where the relevant subset of the model can
be easily identified (Andrea's requirement methinks)
5. Model it precisely yet succinctly (constraint language will help oodles
here)
6. Don't think WE have to model the Universe: Instead provide (decide on) an
appropriate tool set and conventions such that those in the Universe can
effectively (and consistently) model themselves. This is what I see NIM
fundamentally accomplishing.

1+2+3+4+5+6 = 24x80 (for what you are interested in anyway).

Cheers,
-Dave


> -----Original Message-----
> From: Randy Bush [mailto:randy@psg.com]
> Sent: Monday, April 17, 2000 11:36 PM
> To: Andrea Westerinen
> Cc: nim@ops.ietf.org
> Subject: RE: Closing on NIM requirements
> 
> 
> > The data/relationships/methods must be modeled enough, but 
> not too much.
> > So, I always start with the problems being solved 
> (requirements), and move
> > to the nouns and verbs.  I never start with a predefined 
> model in mind.
> 
> well, policy framework started with cim handed down from 
> dmtf, and has been
> trying to recover 'ere since.
> 
> so, what are the requirements here?  for what purpose(s) are 
> we trying to
> model what?  can we get it on one 24x80 screen?
> 
> randy
> 
>