Arrogant RBL list maintainers

Frank Bulk frnkblk at
Wed Dec 9 21:15:57 CST 2009

Each network can decide how they want to run their network, and Trend Micro
can make any list they like, but if wants to send e-mail to other
networks that use Trend Micro's list for spam control, will have
to decide whether to comply with the other network's rules, even if those
rules seem unreasonable.  

Two sides of an SP's coin: I want to maximize my e-mail servers'
deliverability, so I make sure those have appropriately named PTRs and make
sure that outbound messages aren't spammy; I also want to restrict
deliverability of e-mail from my dynamic space, so I have appropriately
named PTRs so that others don't have to guess what kind of host it is.
Perhaps I forgot those customers with static hosts and that want to send
e-mail -- I make sure those PTRs are well-named, too.


-----Original Message-----
From: Seth Mattinen [mailto:sethm at] 
Sent: Wednesday, December 09, 2009 1:24 PM
To: nanog at
Subject: Re: Arrogant RBL list maintainers

Michael Holstein wrote:
> Suit yourself .. but you can't arbitrarily force the Internet as a whole
> to adopt an unwritten standard just to make your lives easier. If we
> encounter problems with our end-users and not being able to deliver
> email reliably to one of your customers, we'll have them call you, since
> we're complying with all the various SPAM prevention standards that
> presently exist.

One could argue that you are *not* complying by using a generic PTR for 
a mail server. Some would say that a serious mail server should have 
proper DNS records, others will say that you should accept mail from any 
IP no matter what.


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