ietf
[Top] [All Lists]

RE: WG Review: NETCONF Data Modeling Language (netmod)

2008-04-22 10:14:56
Eric....

REALLY... ????

I heard during that BOF that there was consensus to start the work.
I also saw that quite a few liked the YANG proposal, and several
wanted to have mappings to either XSD or RELAX or DSDL.

The smaller meetings that happened after the NOF, included people
from all of the proposals that were on the table, including people
who were in teh Design Team for the requirements. We had
fruitfull discussions that converged onto a single approach.

We then got all the people from the various proposls together on
the rdcml mailing list (the one that was used by the requirements
design team), and we had a 2 week long discussion with multiple
hundereds of emails and opinions, and again, we converged to a
common and acceptable draft WG charter.

That draft WG charter was then put to the NGO mailing list were
we had further discussion with various other people. Again we seem
to have consensus. Several non-original-netconf people are on
that mailing list, as a result of the BOF discussions we have had
in the past thow IETF meetings.

Then, Dan brought it to IESG, and the IESG agreed to send the
WG proposal out for IETF Wide review. That is where we are now,
and sure you can vent your opinion, but claiming (or accusing us)
that there was no wide discussion or that there is no consensus at
all and that there were/are just 4 different groups with conflicting
proposals does not seem valid to me.

Further, the change you propose to the WG charter, could be done,.
and then in the first WG session we could declare victory for the
milestone you want. I believe that virtually all of the interested
people were involved in the discussion sofar. So I do not see why
we would need long in a newly formed WG to come to the same
conclusion again.

But if we do what you propose, then we will consume again more
cycles of IESG/IAB and the IETF at large, because they will have
to look once more at the WG rechartering in 3 months time.

Bert Wijnen

-----Oorspronkelijk bericht-----
Van: ietf-bounces(_at_)ietf(_dot_)org 
[mailto:ietf-bounces(_at_)ietf(_dot_)org]Namens Eric
Rescorla
Verzonden: dinsdag 22 april 2008 18:10
Aan: ietf(_at_)ietf(_dot_)org; iesg(_at_)ietf(_dot_)org
Onderwerp: Re: WG Review: NETCONF Data Modeling Language (netmod)


I object to the formation of this WG with this charter.

While there was a clear sense during the BOF that there was interest
in forming a WG, there was absolutely no consensus on technical
direction. Rather, a number of proposals were presented, but no
strawpoll, hum, or sense of the room was taken, nor, as far as I can
determine, has there been any such consensus call been taken on any
list I'm aware of. This wasn't an accident--the BOF was explicitly
intended only to determine whether some work in this area should
proceed, not to select a technical approach.

I understand that an approach like this was proposed in the OPSAREA
meeting by Chris Newman and then that there was a breakout meeting
where it was discussed further. The minutes don't record any consensus
call on this combined direction (only strawpolls on the individual
proposals), and even if such a consensus call had been held, the
OPSAREA meeting would not be the appropriate place for it: this
discussion needs to happen in either the BOF (to allow cross-area
review) or in the designated WG, when it is formed.

Accordingly, if this WG is to be formed, the entire section (and
corresponding milestones) which specifies the technology needs to be
removed. Rather, the first work item should be to select a technical
approach.

-Ekr

NETCONF Data Modeling Language (netmod)
----------------------------------------
Last modified: 2008-04-10

Current Status: Proposed Working Group

Chair(s):

TBD

Operations and Management Area Director(s):
Dan Romascanu <dromasca at avaya.com>
Ronald Bonica rbonica at juniper.net

Mailing Lists:

General Discussion: ngo at ietf.org

Description:

The NETCONF Working Group has completed a base protocol to be
used for configuration management.  However, the NETCONF protocol
does not include a standard content layer.  The specifications do
not include a modeling language or accompanying rules that can be
used to model the management information that is to be configured
using NETCONF. This has resulted in inconsistent syntax and
interoperability problems. The purpose of NETMOD is to support
the ongoing development of IETF and vendor-defined data models
for NETCONF.

NETMOD's requirements are drawn from the RCDML requirements draft
(draft-presuhn-rcdml) and documents referenced therein.


The WG will define a "human-friendly" modeling language defining
the semantics of operational data, configuration data,
notifications, and operations.  This language will focus on
readability and ease of use.  This language must be able to serve
as the normative description of NETCONF data models.  The WG will
use YANG (draft-bjorklund-yang) as its starting point for this
language.

Language abstractions that facilitate model extensibility and
reuse have been identified as a work area and will be considered
as a work item or may be integrated into the YANG document based
on WG consensus.

The WG will define a canonical mapping of this language to
NETCONF XML instance documents, the on-the-wire format of
YANG-defined XML content.  Only data models defined in YANG will
have to adhere to this on-the-wire format.

In order to leverage existing XML tools for validating NETCONF
data in various contexts and also facilitate exchange of data
models and schemas with other IETF working groups, the WG will
define standard mapping rules from YANG to the DSDL data modeling
framework (ISO/IEC 19757) with additional annotations to preserve
semantics.

The initial YANG mapping rules specifications are expressly defined for
NETCONF modeling.  However, there may be future areas of
applicability beyond NETCONF, and the WG must provide suitable
language extensibility mechanisms to allow for such future work.
The NETMOD WG will only address modeling NETCONF devices and the
language extensibility mechanisms.  Any application of YANG to
other protocols is future work.

The WG will consult with the NETCONF WG to ensure that NETMOD's
decision do not conflict with planned work in NETCONF (e.g.,
locking, notifications).

While it is desirable to provide a migration path from existing
MIB modules to YANG data models (modules), it is not a
requirement to provide full compatibility between SMIv2 and YANG.
The Working Group will determine which constructs (e.g., conformance
statements) are not relevant for translation from SMIv2 to YANG. YANG is
also permitted to introduce constructs that cannot be expressed
in SMIv2.
However, all basic types that can be represented in SMIv2 must be
expressible in YANG.

Initial deliverables are below.  The working group may choose to
combine multiple deliverables into a single document where deemed
appropriate.

1. An architecture document explaining the relationship
between YANG and its inputs and outputs. (informational)

2. The YANG data modeling language and semantics (proposed
standard)

3. Mapping rules of YANG to XML instance data in NETCONF
(proposed standard)

4. YIN, a semantically equivalent fully reversible mapping to an
XML-based syntax for YANG.  YIN is simply the data model in an
XML syntax
that can be manipulated using existing XML tools (e.g., XSLT) (proposed
standard)

5. Mapping rules of YANG to DSDL data modeling framework (ISO/IEC
19757), including annotations for DSDL to preserve top-level
semantics during translation (proposed standard).

6. A standard type library for use by YANG (proposed standard)

Goals and Milestones:

Jun 2008 - All _individual_ drafts available that will be used as
input into the WG documents (draft-bjorklund-yang, architecture
draft, YIN draft, YANG standard library draft, DSDL mapping rules
draft)

Aug 2008 - Initial set of WG drafts: architecture, YANG, YIN,
YANG standard library, DSDL mapping rules (if there is one/more
individual draft), based on WG decisions in Dublin

Sep 2008 - Initial DSDL mapping rules document

Oct 2008 - 01 of YANG, DSDL, architecture, YIN, and standard
library draft.  If split out, -00 of on-the-wire XML draft.

Feb 2009 - WGLC for architecture doc

Mar 2009 - Submit the architecture doc to the IESG for
publication as an Informational RFC

Aug 2009 - WGLC for YANG, YIN, XML on-the-wire (if split out),
YANG standard library, DSDL mapping rules

Sep 2009 - Submit YANG, YIN, XML on-the-wire (if split out), YANG
standard library, DSDL mapping rules to the IESG for publication as a
Proposed Standard
_______________________________________________
_______________________________________________
IETF mailing list
IETF(_at_)ietf(_dot_)org
https://www.ietf.org/mailman/listinfo/ietf


_______________________________________________
IETF mailing list
IETF(_at_)ietf(_dot_)org
https://www.ietf.org/mailman/listinfo/ietf