Re: Companies using public IP space owned by others for internal routing

[Mark Andrews <marka () isc org>]

> On 18 Dec 2017, at 1:20 pm, Robert Webb <rwebb () ropeguru com> wrote:
>
> Apologies for not responding sooner.
>
> This came to light with me on a forum where someone posted that they thought it strange that their MTA received an IP 
> that is assigned to the DoD DNIC. 
>
> Where I work I have the opposite issue. They have a lot of public IPv4 space and only use it internally never be 
> advertised to the internet. Something I have never agreed 
> With doing.
>
> Robert

Why?  This is a perfectly legitimate use of the IP addresses.  The purpose of assigning addresses is so that they are 
unique WORLD WIDE in whatever context you wish to use them in.

Mark

> -----Original Message-----
> From: Richard Porter [mailto:richard () pedantictheory com] 
> Sent: Sunday, December 17, 2017 8:25 PM
> To: Robert Webb <rwebb () ropeguru com>
> Cc: nanog () nanog org
> Subject: Re: Companies using public IP space owned by others for internal routing
>
> Robert,
> 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?
>
> ~Richard
>
> > On Dec 17, 2017, at 3:30 PM, Robert Webb <rwebb () ropeguru com> 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

-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742              INTERNET: marka () isc org