On Fri, 2005-08-26 at 09:49 +0100, Dan Field wrote:
- Only useful for FALSE results - i.e.: the sender is forged? So if a
pshiser publishes valid SPF for his domains he can gain a pass... I
suppose this is a benefit in that it is easier to blacklist said
spammer.
The opposite is true. Because forwarding causes failures for SPF, it's
actually only useful in the general case for _positive_ results. You'd
lose genuine mail if you rejected all SPF failures, but you can use SPF
in conjunction with some kind of whitelist.
SPF only reliably tells you 'yes' or 'maybe'.
- Forwarding caused problems unless SRS or some other re-writing is
employed?
The rewriting is never really going to happen in general. SPF will
always give false indications of forgery, while those schemes which
don't require the world to 'upgrade' stand a far better chance than SPF
does.
--
dwmw2