Having tight boundaries may also be non-trivial without making further assumptions about the actual system that uses YANG (data) models.
Personally, I'd be fine with a wording that simply acknowledges that there are grey areas. Michael > -----Original Message----- > From: EXT Juergen Schoenwaelder [mailto:j.schoenwaelder@jacobs- > university.de] > Sent: Sunday, April 10, 2016 5:31 PM > To: Alexander Clemm (alex) > Cc: Carl Moberg (camoberg); Scharf, Michael (Nokia - DE); > [email protected] > Subject: Re: [netmod] YANG model classification? > > This is too abstract for me. There are definitions in > draft-ietf-netmod-yang-model-classification-01.txt - it helps us if > you can tell us which ones are not precise enough or which ones are > missing or which ones you think do not serve a useful purpose. > > All I wanted to say is that boundaries will not be tight and I this is > good as long as we have terms that should ease human communication. > > /js > > On Fri, Apr 08, 2016 at 06:45:01PM +0000, Alexander Clemm (alex) wrote: > > Hi Juergen, the question is still _how_ it simplifies human > communication. To use different terms, it should be clear what > different purposes they convey, and why their distinction is relevant > and matters. IMHO this needs to be articulated more clearly. If it is > not clear why the distinction matters, it does not simplify > communication. > > --- Alex > > > > -----Original Message----- > > From: Juergen Schoenwaelder [mailto:j.schoenwaelder@jacobs- > university.de] > > Sent: Friday, April 08, 2016 12:08 AM > > To: Alexander Clemm (alex) <[email protected]> > > Cc: Carl Moberg (camoberg) <[email protected]>; Scharf, Michael > (Nokia - DE) <[email protected]>; [email protected] > > Subject: Re: [netmod] YANG model classification? > > > > Yes, the boundaries are blurry and it does not matter which layering > model you use. M.3010 does not change the fact that boundaries are > blurry. > > > > I think it is not a problem. My understanding was that the I-D > primarily aims at establish a common vocabulary and it should IMHO > explicitely state that boundaries are blurry and that the main purpose > is to simplify 'human communication'. The classification is not for > 'implementation'. > > > > /js > > > > On Thu, Apr 07, 2016 at 04:43:51PM +0000, Alexander Clemm (alex) > wrote: > > > I am wondering what purpose the classification really serves. At > the end of the day, it seems to me that we are trying to express a > model hierarchy, and articulate what the layers in the hierarchy are. > A device model is thus at a lower layer than a service model. An > implementation of the service model may in turn have dependencies on > the device model, but not the other way round. > > > > > > Where the models are instantiated - on a controller, on a "device", > etc - seems to be secondary and incidental. The boundaries are blurry, > anyways. A controller is a device too; some devices may contain > virtualized controllers, and so on. > > > > > > One model that is relevant in this discussion seems to be the TMN > model, as defined in ITU-T Recommendation M.3010. This model defines a > set of management layers - network element (device), network, service, > business - with well defined funcional scope of each layer. The layers > / function hierarchy also imply an information and data model > hierarchy. > > > > > > Would it make sense to see if the layering in M.3010 could help > guide YANG model classification, and reference those definitions? > > > > > > --- Alex > > > > > > -----Original Message----- > > > From: netmod [mailto:[email protected]] On Behalf Of Carl > Moberg > > > (camoberg) > > > Sent: Thursday, April 07, 2016 1:57 AM > > > To: Scharf, Michael (Nokia - DE) <[email protected]> > > > Cc: [email protected] > > > Subject: Re: [netmod] YANG model classification? > > > > > > > > > > > > -- > > > Carl Moberg > > > Technology Director, CVG > > > [email protected] > > > > > > > On Apr 7, 2016, at 10:55 AM, Scharf, Michael (Nokia - DE) > <[email protected]> wrote: > > > > > > > >> I come at this from the classification angle, so my interest is > if > > > >> the assumption that a YANG model can only be classified as a > > > >> network service model XOR a network device model according to > the > > > >> definitions in draft-ietf-netmod-yang-model-classification > > > >> (sections 2.1 and 2.2). Based on this discussion I take it that > some models are intended to be able to serve in both roles. And we > should make sure that it’s supported in our catalog structure. > > > > > > > > Regarding the XOR assumption for classification: > > > > > > > > You may also want to think about YANG models that are NEITHER > device NOR service models. For instance, what about RFC 6991? And I > think other, more technical models presented this week may fall into a > similar category ("generic"?). > > > > > > Very good point, thanks! That will need some additional thinking > and writing. > > > _______________________________________________ > > > netmod mailing list > > > [email protected] > > > https://www.ietf.org/mailman/listinfo/netmod > > > _______________________________________________ > > > netmod mailing list > > > [email protected] > > > https://www.ietf.org/mailman/listinfo/netmod > > > > -- > > Juergen Schoenwaelder Jacobs University Bremen gGmbH > > Phone: +49 421 200 3587 Campus Ring 1 | 28759 Bremen | > Germany > > Fax: +49 421 200 3103 <http://www.jacobs-university.de/> > > -- > Juergen Schoenwaelder Jacobs University Bremen gGmbH > Phone: +49 421 200 3587 Campus Ring 1 | 28759 Bremen | Germany > Fax: +49 421 200 3103 <http://www.jacobs-university.de/> _______________________________________________ netmod mailing list [email protected] https://www.ietf.org/mailman/listinfo/netmod
