Repeated Blacklisting / IP reputation

Tom Pipes tom.pipes at
Tue Sep 8 14:57:58 UTC 2009


We obtained a direct assigned IP block from ARIN in 2008. This block has been cursed (for lack of a better word) since we obtained it.  It seems like every customer we have added has had repeated issues with being blacklisted by DUL and the cable carriers. (AOL, AT&T, Charter, etc).  I understand there is a process to getting removed, but it seems as if these IPs had been used and abused by the previous owner.  We have done our best to ensure these blocks conform to RFC standards, including the proper use of reverse DNS pointers.

I can resolve the issue very easily by moving these customers over to our other direct assigned block.  In the last year I have done this numerous times and have had no further issues with them.

My question:  Is there some way to clear the reputation of these blocks up, or start over to prevent the amount of time we are spending with each customer troubleshooting unnecessary RBL and reputation blacklisting? 

I have used every opportunity to use the automated removal links from the SMTP rejections, and worked with the RBL operators directly.  Most of what I get are cynical responses and promises that it will be fixed.  

If there is any question, we perform inbound and outbound scanning of all e-mail, even though we know that this appears to be something more relating to the block itself.

Does anyone have any suggestions as to how we can clear this issue up?  Comments on or off list welcome.


Tom Pipes 
T6 Broadband/ 
Essex Telcom Inc 
tom.pipes at 

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