On Jun 18, 2012, at 12:32 PM, Lindsay Haisley wrote:
VERP is not an SMTP protocol, but a MTA property supported by many modern MTAs such as Courier. It relies on the fact that MTAs which support it treat user-somedata@example.com as an email address extension of user@example.com.
Okay, not technically a part of the SMTP protocol, that much I grant.
But there is already enough complexity in getting people to support just plain basic VERP. We don't need to go making the situation more complex than it already is, at least not as it applies to any "standard" implementation.
At least, not yet. Gimme a working implementation that has been demonstrated to avoid tripping all sorts of alarms and falling foul of other standard techniques (e.g., greylisting), and then maybe we can revisit the concept of actually recommending a functional change based on our real-world experience.
-- Brad Knowles <brad@shub-internet.org> LinkedIn Profile: <http://tinyurl.com/y8kpxu>