[Asrg] Re: Asrg Digest, DNSBL BCP v.2.0

[Bill Cole]

At 1:07 PM -0600 3/3/07, Al Iverson wrote:

>With a blacklisting, I get a bounce back and can find somebody to
>argue with. With the common method of implementing a content filter,
>my mail is quietly eaten and I get no information back regarding the
>failure to deliver the mail to end recipient. This is worse than IP
>blacklisting; less transparent; less obvious; less opportunity for
>feedback and investigative recourse.


That's not an uncommon way of deploying content filters, but it is a 
diminishing model. It is increasingly common that what you get is a 
long pause at the end of DATA and then a rejection in SMTP just as 
with DNSBL use, albeit at a later stage. This is essentially 
universal for content filters hooked into Sendmail via its Milter 
interface (now also present in Postfix) or into Postfix via its 
'before queue, external' filter interface.

  It has also not been terribly uncommon for people to deploy DNSBL 
and other IP-based blocking with ill-considered discarding and 
quarantining.


-- 
Bill Cole                                  
bill at scconsult.com