As an ISP'll end up with collisions with their customers if RFC1918 space is used for their intermediary/ISP portion of NAT444, a new /10 (specifically 100.64.0.0/10) was allocated for this use. RFC6598 details the allocation, and the use cases for it.
--
Neil Fenemor | +64 21 978 078 | Facetime | Skype
On 27 February 2014 at 12:00:57 pm, Dave Mill (davemill(a)gmail.com) wrote:
As a slightly more serious reply (though Mike's URL did work surprisingly well..) I would assume we are going to see more and more RFC1918 addresses used by ISPs as IPv4 runs out and CGN is used more.
I'm aware of at least 3 ISPs in NZ doing this (we're one of them to some extent with a couple of our prepay products) and I'd expect there are more.
Cheers
Dave
On Thu, Feb 27, 2014 at 11:55 AM, Mike Cooper