Re: [spring] Spirit and Letter of the Law (was: Question about SRv6 Insert function)

[Tom Herbert <[e-mail]>]

On Thu, Sep 5, 2019 at 6:35 AM Ole Troan <[e-mail]> wrote:
>
> Joel,
>
> > Part of the reason we write restrictions and requirements into RFCs is so that we do not have to repeat the arguments.
> >
> > If the proponents of the insertion have arguments for why it is now okay, they need to make those arguments.  And they need to make sure that the discussion is taken to the relevant working groups.  The burden should not be on those who are asking that attention be paid to existing RFCs.
>
> As far as I know, but I'm trying to stay away from the actual proposals and argue this generally, no-one is proposing to update the RFC8200 header insertion text.
> What people are proposing are for specific domains. And given that, I believe people need to argue the technical merits of those specific proposals.

Ole,

I don't believe the requirements of RFC8200 were ever intended to be
conditional based on the runtime environment. Either it's IPv6 or it's
not. I would be opposed to bifurcating standard protocols so that they
work differently in the open Internet versus a limited domain.

> As opposed to throwing the "law book" around.

This is isn't just throwing the law book around. Consider that
extension header insertion was proposed in
draft-voyer-6man-extension-header-insertion and there was much
discussion on the list. There were a number of very specific arguments
articulated why this is not robust and how this can break other
protocols. I don't see that the proponents of haven't provided counter
arguments. So I believe that the current consensus is that EH
insertion is not allowed, but that 's not just because RFC8200 says so
but also because there are material reasons why it's a bad idea. This
doesn't preclude the possibility of the EH insertion could be accepted
some day, but I don't see how that can happen unless the arguments
against it are addressed.

Tom


>

> Best regards,
> Ole
>
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