RE: The anti-abuse rDNS check that FTP gave up

["Murray S. Kucherawy" <msk@xxxxxxxxxxxxx>]

> -----Original Message-----
> From: owner-ietf-smtp@xxxxxxxxxxxx [mailto:owner-ietf-smtp@xxxxxxxxxxxx] On Behalf Of Rosenwald, Jordan
> Sent: Wednesday, October 05, 2011 6:40 AM
> To: SMTP Interest Group
> Subject: RE: The anti-abuse rDNS check that FTP gave up
> 
> True statement on both accounts.  I'd add to it, that invalid rDNS is
> still a viable anti-abuse mechanism.  There are plenty of compromised
> machine operators that are "asleep at the wheel."  Checking rDNS
> scrapes off that chaff.

I generally agree, but implementing it on my small site with only a handful of users did lead to a number of false positive complaints that then needed to be handled.

It's probably not a good idea to standardize such a practice (yet?), but it does seem like a useful tool to have around.