On Thu, 22 Jan 2004, Marc Alaia wrote:
I am/was trying to say this and only this:
1) SPF checking should NOT be done at SMTP time. It is less intrusive to
the entire installed base of email infrastructure to process an email AFTER
it as been accepted. In this way, it can be processed along with other
spam-related checks. And,
2) The major argument for processing SPF at SMTP time has been bandwith and
processing savings, which I believe are MINIMAL for non-ISP's.
Bandwidth may be minimal for many people. But that isn't the only concern
related to filtering later.
However, I want to be able to drop messages before the message is received
to I can short circuit the additional filters which cost me a lot in
server load when I get a large amount of email come through. If I accept
the message, I have to spool it so I don't lose the message if it's legit
and the server happens to crash. That means I have to store it for
whatever period of time before I drop it if its junk. The more junk I can
refuse at MAIL FROM <> time even RCPT TO time, the less likely I'll have
to spend cash I don't have to upgrade my mail server hardware.
Admittedly, running a filter of some kind during the SMTP dialogue as well
as running a filter after the message is accepted adds complexity. But it
does reduce load on my servers because they no longer have to process the
message at all if it is dropped at the first stage.
If you don't want to run checks at SMTP time, then don't. I don't see
anyone advocating that you have to run the SPF checks at SMTP time on
your mail server. But I want to reject stuff as soon as possible. That
means I want to run SPF at SMTP time before DATA.
--
William Astle
finger lost(_at_)l-w(_dot_)net for further information
Geek Code V3.12: GCS/M/S d- s+:+ !a C++ UL++++$ P++ L+++ !E W++ !N w--- !O
!M PS PE V-- Y+ PGP t+@ 5++ X !R tv+@ b+++@ !DI D? G e++ h+ y?
-------
Sender Permitted From: http://spf.pobox.com/
Archives at http://archives.listbox.com/spf-discuss/current/
Latest draft at http://spf.pobox.com/draft-mengwong-spf-02.9.4.txt
To unsubscribe, change your address, or temporarily deactivate your
subscription,
please go to
http://v2.listbox.com/member/?listname(_at_)©#«Mo\¯HÝÜîU;±¤Ö¤Íµø?¡