Address Assignment Question
jerome at ceriz.fr
Mon Jun 20 22:16:22 UTC 2011
2011/6/20 John Levine <johnl at iecc.com>:
> Hi. I'm the guy who wrote the CEAS paper on greylisting.
> Greylisting is useful, but anyone who thinks it's a substitute for
> DNSBLs has never run a large mail system.
You're right, greylisting on a large system may not be efficient as it
won't block everything and will eat-up quite a lot of system
ressources. But it's a good start once basic protocol-checks have
already eliminated the 80% amount of bullshit sent from botnets.
My point is : combining server-side checks of different nature is
often enough to avoid the use of RBLs and still provide a goode
quality of service. It probably won't scale to comcast' or AOL' MXs
but it's way better than relying on an external authority for your
corporate or personnal mailserver.
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