Companies using public IP space owned by others for internal routing

James Downs egon at
Sun Dec 17 22:57:28 CST 2017

> On Dec 17, 2017, at 14:33, Matt Hoppes <mattlists at> wrote:
> Had a previous employee or I discovered it on the network segment after we had some weird routing issues and had to get that cleaned up. I don't know why anyone would do that when there is tons of private IP space.

Unless there isn't.. I've worked at more than one company that had used up all the private space. Then you have the cases where some M&A causes overlapping IP space. In addition, you'd also be surprised how many people just assign the entire 10/8 space into a flat IP space.


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