Hi Martin, You may have just seen my comment to Juergen, but with an AD hat on, I think that what you propose is not a valid option.
My understanding is that the IETF process does not allow an RFC to choose to ignore a MUST statement in another RFC for pragmatic reasons (I would DISCUSS on this and suspect that many other ADs would as well). If you are sometimes allowed to ignore the rule then one would correctly argue that would be a SHOULD not a MUST ... If the goal is to have the module update rules of RFC 7950 be interpreted differently then the only choices are to bis RFC 7950 or write another RFC that updates it. I currently allow the RFC 7950 module update rules to be interpreted pragmatically on the understanding that the RFC 7950 rules would be loosened to allow it. Regards, Rob > -----Original Message----- > From: netmod <[email protected]> On Behalf Of Martin Björklund > Sent: 18 July 2023 04:48 > To: [email protected] > Cc: [email protected] > Subject: Re: [netmod] YANG Versioning: Key Issue #1 - Allow NBC changes in > YANG 1.0 & YANG 1.1 or not? > > What about Option 4 - Pragmatic Adherence to Current RFC7950 Rules > > - As it works today; the IETF *has* published bugfixed modules that break > the > rules. (and many vendors do this as well) > - (Possibly) Introduce rev:non-backwards-compatible > > This would allow 6991bis to update date-and-time to follow the updated > semantics for RFC3339 timestamps (which imo is the only reasonable > thing to do - the consuequences of this change is handled by SEDATE). > > > /martin > > "Jason Sterne (Nokia)" <[email protected]> wrote: > > Hi all, > > > > At the request of the NETMOD chairs, and on behalf of the YANG > Versioning weekly call group, here's a summary of Key Issue #1 for the > versioning work (i.e. for the Module Versioning and YANG Semver WGLC). > > > > We'd like to suggest that the WG has a strong focus on deciding on this > specific issue first. Then we'll move on to tackle other key issues. The idea > is > to try and avoid getting tangled in a web of multiple intertwined issues. > > > > Key Issue #1 is the following: Allow NBC changes in YANG 1.0 & YANG 1.1 > or not? > > > > For now please avoid debating other issues in this thread (e.g. multiple vs > single label schemes, whether YANG semver is a good scheme, etc). Let's > focus on K1 and work towards a WG decision. > > > > ################################### > > K1) Allow NBC changes in YANG 1.0 & YANG 1.1 or not? > > > > Option 1 - Update RFC7950 to Allow NBC Changes > > ----------------------------------------------------------------------- > > - Module Versioning modifies 7950 to allow NBC changes > > - guidance that NBC changes SHOULD NOT be done (impact to user base) > > - rev:non-backwards-compatible is a YANG extension > > - introduction in published YANG does not impact current tooling > (ignored until recognized) > > PROS: > > - address fundamental requirement of this versioning work (requirements > doc) > > - allows gradual adoption in the industry. YANG authors can immeditately > start publishing with the new extensions. > > - move faster to produce modules in the IETF (accept some > errors/iteration) > > - address the liaison from external standards bodies in a reasonable > timeframe > > - authors believe work is ready > > - broad vendor support > > - rough alignment with OpenConfig (use YANG 1.0 + OC Semver) > > CONS: > > - perception that we're "cheating" by not bumping our own spec's version > > - Not fundamentally mandatory for clients or servers using YANG > (mandatory for YANG claiming conformance to Module Versioning). > > > > Option 2 - RFC7950-bis: Publish a new version of the YANG language to > allow NBC changes > > ----------------------------------------------------------------------- > > - NBC changes only allowed in a new (future) version of YANG > > - TBD: YANG 1.2 vs 2.0 (note YANG 1.1 isn't BC with YANG 1.0) > > - Content = Module Versioning + YANG Semver + very limited YANG NEXT > items > > - rev:non-backwards-compatible tag is a language keyword > > - consequence: any use of it breaks all YANG 1.0/1.1 tooling that hasn't > been updated > > - TBD how to handle small NBC changes in IETF in the short term (i.e. non > conformance to 7950)? > > - RFC6991 bis - change the use/meaning of ip-address (or change > datetime) > > - YANG date-and-time (because of SEDATE date string changes) > > > > PROS: > > - address fundamental requirement of this versioning work (requirements > doc) > > - clear delineation of changes in the YANG language > > - consistent with philosophy that version number changes for significant > changes in a spec (avoids concern that YANG is changing without bumping > the version of YANG) > > - can do this with mandatory YANG keywords which helps increase > conformance to the new rules > > CONS: > > - difficult to roll out in the industry. Tools need upgrading before they > won't error on a YANG 1.2 module. > > - Authors can't publish YANG 1.2 until their users have upgraded their > tools. Everyone has to move at once. > > - likely large delay in producing the work (unclear what would go into > YANG 1.2, may not reach concensus easily on N items) > > - delay in follow up work (Packages, Schema Comparison, Version > Selection) > > - continue dominating WG effort for longer (opportunity cost) > > > > Option 3 - Strict Adherence to Current RFC7950 Rules > > ----------------------------------------------------------------------- > > - IESG will be unable to approve any RFCs that make any changes to IETF > YANG modules that don't strictly conform to those rules > > - RFC6991 bis would not be allowed to change the use/meaning of ip- > address (or change datetime) > > - YANG date-and-time couldn't change (related to SEDATE date > string changes) > > PROS: > > - clear rules for entire industry including IETF > > CONS: > > - doesn't address agreed/adopted requirements of YANG versioning work > > - incorrect assumption in tool chains, etc that NBC changes don't happen. > Silent failures. > > > > Jason (he/him) > > > > _______________________________________________ > netmod mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/netmod _______________________________________________ netmod mailing list [email protected] https://www.ietf.org/mailman/listinfo/netmod
