At 09:51 PM 6/8/2004 -0400, you wrote:
- Any policy engine that operates after the end of DATA is largely a waste
of effort. Existing post-acceptance message filtering tools are extremely
effective. If we discover a forgery after accepting a message, we can't
send a DSN since the return-path is dubious so we are forced to null route
the message. Though this is clearly the lesser of two evils, it highly
undesirable.
- Once a message passes 2821 tests and we allow the SMTP-client to proceed
to DATA, it is to our advantage to identify any _inexpensive_ tests that can
be done that permit us to reject at the end of DATA. We should look for
these opportunities because it is better to reject at the end of DATA than
to discover the problem later and silently drop the message.
--
Seth Goodman
**************** REPLY SEPARATER *****************
Any protocol that encourages (alias for permits) background processing
after DATA (ie. bounce) is plain WRONG. The biggies will take this approach
every time because it evens out the processing load, and we are back to the
old problem of bombarding innocent third parties. Once you allow processing
to occur after DATA, then you have no way to encourage inline processing.
J.A. Coutts