[Jool-list] Node-based translation with LTE

[Tore Anderson]

On 06/02/24 13:43, Mosbeck Martin via Jool-list wrote:
> Hello everyone,
>
> thanks for this great tool and the amazingly good documentation!
>
> I have a question regarding node-based translation (as described in
> https://nicmx.github.io/Jool/en/node-based-translation.html). I would
> like to
> use this for a router which has a public IPv6 LTE connection and clients
> connected to it via a private IPv4 LAN. Both router and clients have
> applications with hardcoded IPv4 addresses.
>
> I’m wondering what to choose as the "proxy address for the private Jool's
> traffic" (2001:db8:1::3 in the example). From first experiments - which
> worked
> nicely - I understand, this address is not really private, but used in
> packets
> sent via the Internet. From my LTE provider I get an IPv6 address with a /64
> prefix. Can I just pick any address inside this /64 subnet without risking
> address collisions with someone else? Can I be sure that any IPv6 LTE
> provider
> always offers me some range of addresses rather than only a single one?

Hi Martin,

You can rely on having a whole /64 assigned to you, this is mandated by 
the 3GPP standards. You are free to use a secondary address within the 
/64 as your the CLAT address.

The ModemManager documentation contains a very nice overview on how IPv6 
(and IPv4) assignment happens in LTE networks, I suspect you might find 
it interesting:

https://modemmanager.org/docs/modemmanager/ip-connectivity-setup-in-lte-modems/

Tore