Re: [Int-area] Introducing IPv4 Unicast Extensions with new draft-schoen-intarea-lowest-address

[Derek Fawcus <[e-mail]>]

On Tue, Aug 03, 2021 at 02:43:10AM -0700, John Gilmore wrote:
> Our team successfully patched both Linux and BSD over a few weeks, and
> interoperated them successfully.

Linux doesn't need a patch, just a configuration change
(use the 'ip' command to delete the 0-host address/prefix).

I know because a number of years ago I did this with my home set up
where my ISP proveded a /29, and I used all 8 addresses without NAT.

As I recall, I did something like using a RFC 1918 prefix as the
attached net to an interface, and installed a static /28 route for
the public prefix to the same interface on the router (so it would ARP).

Then it was simply a question of how to get the various hosts to
initiate outgoing connections using that public address.  Linux was
easy, as one can specify the source address for the default route.

One one box I used a tunnel to the edge router to achieve a similar effect.

I imagine there are a few ways to achieve these w/o forcing use of NAT.

So operationally one can reclaim both the all-0 and all-1 host
addresses _now_, if one knows what one is doing.  So while I don't
object to the change, I don't view it as freeing up addresses which
can't already be used.

DF