[GTALUG] odd DHCP participant on Rogers cable internet

[Lennart Sorensen]

On Fri, Oct 23, 2015 at 11:39:12AM -0400, D. Hugh Redelmeier wrote:
> 7.11.164.145 is not in 7.0.0.0/16.

Hmm, nope that is true.

I wonder if someone at rogers is simply changing 10 to 7 without making
sure to stay in the valid range.

> Is it the case that the /8 is completely unrouted?
> 
> According to the NTT Lookinglass, the router in Ashburn VA sees no network 
> in its BGP table for 7.11.164.145.  So I guess it is safe.
> 
> <http://www.us.ntt.net/support/looking-glass/>

A bit more searching does seem to say that the entire 7.0.0.0/8 block
is not routeable from the normal internet, so rogers apparently was told
by IANA they could use them internally as long as they did not allow
traffic to or from those addresses outside of rogers.

-- 
Len Sorensen