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

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

Looks pretty good.  A few minor points:

In section 3, I think that you should point out that a in a successful
greylister, all the regular correspondents will be whitelisted, so the
only mail that is delayed is mail from an IP that has never sent mail
before, or sent mail so long ago that it's fallen out of the
whitelist.  In mail systems I've used, the vast majority of mail comes
from places on the whitelist, so after a training period (which you
can fake by watching traffic before you turn on the greylister and
seed the whitelist with all the addresses you've seen) only a small
proportion of mail should be affected.

In section 3 and again in section 9.2, it refers to the size of the
database.  My total database is under 40,000 entries, including 92
IPv6 addresses.  I expect a larger system would have a larger
database, but it would be a pretty feeble server that would have
trouble with a table even ten times that size.  My manual whitelist
has 62 entries, mostly CIDR ranges, probably half of which are stale
but there's not much incentive to clean it out.

R's,
John