Patrik Faltstrom (pfaltstr) wrote:
Difficult...the whole idea with grey listing is that smtp server
that receive mail is using corners of the protocol that smtp servers
have implemented but not spam serving software.
Difficult but in my view doable with a possible high payoff for everyone.
Exactly where and what that difference is will always differ over
time, and by definition can not be standardized.
So, what to include in such a draft?
How to act in the case of 4xx? How to format 4xx responses?
Yes, I think that would be the only reasonable "major benefit" to
consider in such a draft - i.e. a "method" that can really help systems.
But I can also see where we (the industry) now has enough years into
GL implementation and we have history and recommendations to be outlined.
- Intro and background
- Remind people that TIMELY DELIVERY is still important
- Mapping GL Entities (i.e. the triplet vs other factors)
- Class C issues
- Sender vs RFC5322 content (i.e. Message-ID)
- Where in the SMTP state machine 4yz GL rejections
- Connection vs RCPT vs increasingly at DATA
- Recommended Delays
- Recommended Structured Formats for Responses
- Extended Reply codes RFC2034 Considerations
It might be interesting technical reading for all and it might even
useful for new people implementing Greylisting in their operations.