On 9/28/20 4:38 AM, Laura Atkins wrote:
Do you think if the wording in the RFC is changed that established
behavior will change? That the SMTP servers will be reconfigured to
stop doing what they are doing?
I think most operators will not bother to change their existing
practices if/when the RFC wording changes. But if the RFC recommends
poor practice, it will be harder to change that poor practice, because
some people will say "but the RFC says...!" So the RFC should not
recommend poor practice.
If, OTOH, the RFC recommends NOT filtering based on EHLO arguments, then
it will be at least a bit easier for operators to stop doing that when
they start seeing that it's a bad idea.
I'm thinking long term here. I expect 5321bis, if we do our jobs
right, to be around for decades. So its recommendations need to make
sense in the long term rather than the short term.
It doesn't actually bother me that much if existing operators filter
based on EHLO validation as long as they re-evaluate that policy over
time. I expect operators to be pragmatists. But I really do expect
use of NAT64 to increase, and I really think it's unhelpful to network
operators if reliable email operation requires them all to maintain
static IPv4 addresses and connections to the public IPv4 Internet.
It's silly for email to delay a transition away from IPv4 for this reason.
ietf-smtp mailing list