Re: [apps-discuss] Comments on draft-ietf-appsawg-greylisting-04

["John Levine" <[e-mail]>]

>I've added this paragraph to the bottom of Section 3:
>
>   Presuming that known friendly senders will be manually configured as
>   exceptions to the greylisting check,

see below

> a steady state will eventually
>   be reached wherein the only mail that is delayed is mail from an IP
>   address that has never sent mail before.  Experience suggests that
>   the, the vast majority of mail comes from places on such a developed
>   exception list, so after a training period, only a small proportion
>   of mail is actually affected.  The training period could be replaced
>   by processing a history of email traffic and adding the IP addresses
>   from which most traffic arrives to the exception list.
>
>Does that cover it?

The only sources that need to be configured manually are ones that
either don't retry in a way the greylister will recognize, or send so
rarely that they'll age out of the exception list.  Any normal sender
will enter the exception list the first time it retries, and never
leave.

>Added this to the end of 9.2, same question:
>
>   In practice, this has not appeared as a serious concern, because any
>   reasonable aging policy successfully moderates database growth.  It
>   is nevertheless identified here as a consideration as there may be
>   implementations in some environments where this is indeed an issue.

Sure.  I suppose a greylister in an embedded device might have space constraints.

R's,
John