Re: [v6ops] IPREF as a transitioning tool

["Soni \"They/Them\" L." <[e-mail]>]

On 2023-11-12 08:18, Gert Doering wrote:
> Hi,
>
> On Sun, Nov 12, 2023 at 08:07:12AM -0300, Soni "They/Them" L. wrote:
> > > For server setups, SIIT-DC seems to work well (and server applications
> > > are usually better controlled and can be taught to use v6 sockets).
> > > 
> > > What scenarios do you have in mind where a 464xlat on the server itself
> > > would be beneficial, as compared to a v6-only datacenter with SIIT-DC in
> > > front?
> > 
> > SIIT-DC appears to use the same packet translation building blocks as
> > 464XLAT/NAT64...? (From skimming, it looks like the same thing, just with
> > different names for the various components! And the addition of a "reverse"
> > mode of operation, where it accepts connections from v4 hosts.)
>
> Yes.  Basically, IPv6 only (as in a mobile network) but with IPv4->IPv6
> translation at the edge, so IPv4 clients can reach IPv6-only servers
> (= "publically visible services" appear dual-stacked, with v4 going
> through the translator)
>
> > So what makes 464XLAT (on *top* of SIIT-DC, as opposed to replacing it)
> > better is the ability to let the server know about it. As well as being able
> > to standardize on a protocol already supported by (some) operating systems
> > (systemd is slowly working on adding a CLAT, and FreeBSD allegedly already
> > has one).
>
> Not sure why this is a benefit for the server.  Assuming a v6-only world,
> and not having to care any bit about v4 or translation technologies sounds
> like a great benefit.
>
> So, asking again - why do you think it would be beneficial if the server
> had to care?
>
> (On a *Client*, which is where systemd seems to be evolving Linux to,
> local 464xlat brings obvious benefits to v4-only applications)

Because DNS64 is a crime (sometimes literally, but often at least breach 
of contract, because it breaks DNSSEC) and 464XLAT lets you avoid it. 
And on a server, you might wanna run NixOS, which depends on github and 
that's still IPv4-only.

>
> Gert Doering
>          -- NetMaster