Companies using public IP space owned by others for internal routing

Harry McGregor hmcgregor at
Mon Dec 18 01:56:33 CST 2017


I know of some enterprise IT equipment that does this.  It was reserved space at the time it was picked.

It does not leak from the box, but every once in a while one of these IPs show up in a customer visible log, and causes confusion.

In ways it is better then rfc 1918 space as it has less chance of conflicting with a management network.


On December 17, 2017 3:42:48 PM MST, Richard <rgolodner at> wrote:
>On 12/17/2017 04:30 PM, Robert Webb wrote:
>> Will anyone comment on the practice of large enterprises using non
>RFC1918 IP space that other entities are assigned by ARIN for internal
>> Just curious as to how wide spread this might be. I just heard of
>this happening with a large ISP and never really thought about it until
>> Robert
>     It is more common than you would think. Why use public IP's when 
>you can have many rfc1918 options. Always amazes me after the initial 
>     Richard

Sent from my Android device with K-9 Mail. Please excuse my brevity.

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