Unfortunately Apple's IPv6-only 3GPP support in iOS requires the mobile operator to have a separate tethering APN (as T-Mobile does). There is no other way to get IPv4 connectivity to IPv4-only tethered devices. Since there is no 464XLAT interface in iOS it is not possible to provide IPv4 connectivity on a tethering LAN via an IPv6-only APN connection. There are two operational issues with this for providers. 1) Separate APN providers like T-Mobile have the problem of not being able to provide IPv6 on their tethering LAN without also making their tethering APN dual-stack which is counter to the objective of IPv6-only APNs. 2) Operators with a combined handset and tethering APN cannot provide IPv4 tethering with an IPv6-only APN due to the missing 464XLAT function.
I've been using T-Mobile's 5G home gateway, and for most of what I do, it works well. I've used it for many Zoom calls. AFAIK, they have all been IPv4, so the 464 XLAT has done its job. That said, I wonder if T-Mobile didn't make a big show of creating an IPv6 only last mile in a communications system that doesn't even look at the level 3 address just to get a corner on the network engineer market.
Unfortunately Apple's IPv6-only 3GPP support in iOS requires the mobile operator to have a separate tethering APN (as T-Mobile does). There is no other way to get IPv4 connectivity to IPv4-only tethered devices. Since there is no 464XLAT interface in iOS it is not possible to provide IPv4 connectivity on a tethering LAN via an IPv6-only APN connection. There are two operational issues with this for providers. 1) Separate APN providers like T-Mobile have the problem of not being able to provide IPv6 on their tethering LAN without also making their tethering APN dual-stack which is counter to the objective of IPv6-only APNs. 2) Operators with a combined handset and tethering APN cannot provide IPv4 tethering with an IPv6-only APN due to the missing 464XLAT function.
I've been using T-Mobile's 5G home gateway, and for most of what I do, it works well. I've used it for many Zoom calls. AFAIK, they have all been IPv4, so the 464 XLAT has done its job.
That said, I wonder if T-Mobile didn't make a big show of creating an IPv6 only last mile in a communications system that doesn't even look at the level 3 address just to get a corner on the network engineer market.
This was a very comprehensive review that any carrier (as well as enterprises) should review before the go V6. Well done.
I really enjoy the info!
Great to see you up there Stephan! Go V6!
Thanks for the upload, lots of good info!