Companies using public IP space owned by others for internal routing

Richard Porter richard at
Mon Dec 18 01:24:40 CST 2017

I’ve heard of two cases recently, large companies (non carrier/ISP). One company looking to solve challenge with IPv6 and 6to4 and DNS.

Also curious how wide-spread this is? Maybe just the kick in the butt for catching the elusive IPv6 unicorn?


> On Dec 17, 2017, at 3:30 PM, Robert Webb <rwebb at> wrote:
> Will anyone comment on the practice of large enterprises using non RFC1918 IP space that other entities are assigned by ARIN for internal routing?
> 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 now.
> Robert

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