David Wilson wrote:
The only problem with not sending 5xx (or not sending a DSN) could be
with false positives. However, I believe this is a very small problem,
at least for the majority of users, and the danger of using 5xx is
significantly greater.
Our experience, issuing 55x at levels of 250,000-1,300,000 per day since
1997 indicates exactly the reverse.
Certainly, there's no way to prove that "it" (an infection) hasn't
happened, but considering we've had precisely _one_ report of a 55x (for
any reason whatsoever) landing in the forgee's mailbox in all that time,
it can't be significant. In contrast to the dozen or so FPs per day
that we do handle. Silently dropping emails would mean that those dozen
or so FPs would go unnoticed by anyone.
_______________________________________________
Asrg mailing list
Asrg(_at_)irtf(_dot_)org
http://www.irtf.org/mailman/listinfo/asrg