Re: [Sidrops] Requiring Two Implementations - before exit of WGLC

[Geoff Huston <[e-mail]>]

> On 24 Jul 2023, at 5:53 pm, Christopher Morrow <[e-mail]> wrote:
> 
> Howdy WG Folks,
> Today SIDROPS has no requirement, except tacitly, to to have working
> and interoperable implementations of the proposed changes.
> 
> Two (or more) times now we've had a request and discussion about
> requiring formally that there be interoperable implementations of the
> protocols/software being standardized. There have been more than one
> instance where our software/protocols are put into use and we found
> some bad interactions :(
> 
> There was some chat at the meeting about this, but I think re-having
> that here is in order.
> Please take some time to consider whether or not this is a healthy
> requirement AND how we may implement it, for instance:
> 
>  "Discussion and finalization of the draft happens, before exit of
> WGLC 2 implementations must be prepared and show interoperability
> (document this on sidrops-wiki with an implementation report) before
> exit of WGLC and being sent for publication."
> 

What I (approximately) said at the mic when this topic was mentioned:

I don't think there is a clear answer to this question and that leads me to
question the wisdom of introducing a _strict_ requirement for multiple
independent interoperable implementations. Yes it can be helpful as a sanity
check of the specification, but at the same time the implementor of the
draft is taking a big risk in that they are chasing shifting sand!

I have heard folk bemoan and argue against further changes to a draft on the
basis that having generated an implementation there is less motivation to
make changes as the draft undergoes the various tweaks and revisions that
occur in a specification progress through the working group and various
reviews and last calls. These early implementations may become a drag weight for
the working group in contemplating further changes to a draft specification.

At the same time, text is cheap, and feedback from early implementations can
assist in the quality of a specification.

So I don't think there is a single simple answer here, and I would hope that
there remains some space for discretion and flexibility here, at the cost
of making some work for the chairs in working out what works best in each
case! After all, thats why the chairs get paid all the the big bucks! ;-)

thanks,

  Geoff