Address Assignment Question

Leo Bicknell bicknell at
Mon Jun 20 13:18:44 UTC 2011

In a message written on Mon, Jun 20, 2011 at 08:06:44AM -0500, Jason Baugher wrote:
> Did everyone miss that the customer didn't request a /24, they requested 
> a "/24s worth in even more dis-contiguous blocks". I can only think of 
> one reason why a customer would specifically ask for that. They are 
> concerned that they'll get blacklisted. They're hoping if they do, it 
> will be a small block of many rather than one entire block.


Almost every customer I've dealt with who requested such a thing
eventually ended up having their contract terminated for spamming.

Many of the RBL's chose to increase the size of their blocks to put
more pressure on ISP's.  So if you give them /29's in 10 different
blocks they will block the /24 in each, then a /23 in each, and so
on.  Basically this becomes a quick way for you to get 100% of your
address space blocked, and make the rest of your customers really
unhappy.  When the RBL's see you gave them a bunch of small blocks
in different supernets they assume you are spammer friendly.

       Leo Bicknell - bicknell at - CCIE 3440
        PGP keys at
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