Re: [yam] AD DISCUSS about Section 8 of draft-ietf-yam-rfc4409bis-02 - Message Modifications

[Barry Leiba <[e-mail]>]

>> This is a pretty classic case of avoiding a problematic Discuss, through
>> an easy expedient.
>
> If YAM WG participants view it as such a case, they can voice their concern.

It seems to me, SM, that that's exactly what's happening.

> Dave suggested the following text:
>
>   "Message modification can affect the validity of an existing message
>    signature, such as by DKIM [DKIM], PGP [RFC4880], and can render the
>    signature invalid.  This, in turn, can affect message handling by later
>    receivers, such as filtering engines that consider the presence or
>    absence of a signature"

And I think that text is good.  I support changing the text to this,
and telling Russ that the WG is strongly in favour of having this in
there.  (And I'm not in favour of SM's suggested change to it.)

Having text such as this is important:
This is a common case, where something needs to progress on the
standards track, but something else has come along in the interim that
(1) does not change the existing protocol that's progressing, but (2)
implementors of the existing protocol now need to be aware of.

We're not changing the protocol, but it's critical that anyone looking
at the new Message Submission spec be aware of its effect on
signatures.  We MUST NOT remove this alert.

Barry