It's been 20 years today (Oct 16, UTC). Hard to believe.

Florian Weimer fw at
Wed Oct 17 19:41:24 UTC 2018

* Scott Brim:

> On Tue, Oct 16, 2018, 22:37 Michael Thomas <mike at> wrote:
>> I believe that the IETF party line these days is that Postel was wrong
>> on this point. Security is one consideration, but there are others.
>> Mike
> I saw just a small swing of the pendulum toward the center, a nuanced
> meaning for "liberal". The adage wasn't tossed out. Operationally it can't
> be.

I think DMARC, as it is deployed right now, pretty much killed the
“liberal” part for many people.  It's sender policy, but it's
necessarily enforced at the recipient end, but many recipients aren't
given a choice to opt out when it is technically the wrong thing to
do.  You can switch email providers, but as the IETF never really
designed for email address portability, that's a theoretical option
only for many.

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