Address Assignment Question

Steve Richardson steverich.nanog at
Mon Jun 20 13:26:30 UTC 2011

Hi Jason,

On Mon, Jun 20, 2011 at 9:06 AM, Jason Baugher <jason at> 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.
> When customers make strange requests without giving a good explanation, I
> have to assume they're up to something.
> Jason

They provided an explanation, describing how the IPs were going to be
used.  Yes, part of it does have to do with being blocked, which
*definitely* concerns me.  One thing they do say is that they need
several IPs per block to assign to their MTAs to handle such a large
amount of email (3 to 5 million per day).  Being primarily focused on
layers 1 through 4, I don't have an incredible amount of experience
with high volume email server configuration, so I have no idea if they
are feeding me a line of BS or not.

My feeling is that (paraphrasing here) "we might get blocked
occasionally" and "we need this many IPs on our MTAs because they
can't handle the load" are *not* legitimate reasons for requesting so
many addresses.


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