4 ms·

What is the idea of 464XLAT? We have IoT style devices using AWS. And IPv6 has long not really been available on AWS. Yeah, it has become a bit better the last

What is the idea of 464XLAT? We have IoT style devices using AWS. And IPv6 has long not really been available on AWS. Yeah, it has become a bit better the last 3-5 years. So we have not really worked on IPv6 for our devices either. The kernel would support it, but our user space just does not use it. The typical excuse, someone else hasn't done their homework first... Our devices work just fine with T-Mobile US SIMs. I assume you were referring to US? So where is the IPv6 only aspect?

zamadatix 5y ago
In 464XLAT something on the client side (be it say Android phone itself or TMobile home router) acts as a CLAT to translate local v4 to v6. On the T-Mobile egress it'll act as a PLAT and convert back. There is some other glue to make these two work together. They had a good NANOG talk on it a few years back https://youtu.be/Xl-hIyZSAmA https://youtu.be/Xl-hIyZSAmA For other offerings like NB-IoT or business PCN you're still able to do either it's just the normal consumer services that were pushed to v6 only service. Though I'm not sure if there are still any legacy connectivity options that will fallback to v4.
- usr1106 5y ago
  That's interesting. We use a Sierra Wireless EM 7455 (IIRC, not in work mode now...) with generic global firmware. I am 100% sure our software performs no 4 to 6 translation. So it would need to be in the modem. But that would mean it needs to be a standardized operator-independent protocol. Never heard that such thing exists. > I'm not sure if there are still any legacy connectivity options that will fallback to v4. That sounds the most likely option to me. PS. Not able to watch the video now. Hope not to forget at a more suitable moment.
  - Dagger2 5y ago
    464xlat is standardized and can be set up automatically. All it needs is a DNS query to any v4-only hostname to detect if DNS64 is in operation. Most 4g modems work as routers exposing an ethernet interface to the host, so it's certainly possible that it's doing 464xlat in the firmware, and if it doesn't tell you on some sort of status page then the only real hint that it's doing it would be a reduced path MTU. I wouldn't be surprised if T-Mobile offer legacy service to any type of business contract or non-phone client though.
    - usr1106 5y ago
      > Most 4g modems work as routers exposing an ethernet interface Not idea about most. I have seen it that way, but our Sierra Wireless requires ModemManager and appears as a wwan network interface.

zamadatix 5y ago

In 464XLAT something on the client side (be it say Android phone itself or TMobile home router) acts as a CLAT to translate local v4 to v6. On the T-Mobile egress it'll act as a PLAT and convert back. There is some other glue to make these two work together. They had a good NANOG talk on it a few years back https://youtu.be/Xl-hIyZSAmA https://youtu.be/Xl-hIyZSAmA For other offerings like NB-IoT or business PCN you're still able to do either it's just the normal consumer services that were pushed to v6 only service. Though I'm not sure if there are still any legacy connectivity options that will fallback to v4.

usr1106 5y ago
That's interesting. We use a Sierra Wireless EM 7455 (IIRC, not in work mode now...) with generic global firmware. I am 100% sure our software performs no 4 to 6 translation. So it would need to be in the modem. But that would mean it needs to be a standardized operator-independent protocol. Never heard that such thing exists. > I'm not sure if there are still any legacy connectivity options that will fallback to v4. That sounds the most likely option to me. PS. Not able to watch the video now. Hope not to forget at a more suitable moment.
- Dagger2 5y ago
  464xlat is standardized and can be set up automatically. All it needs is a DNS query to any v4-only hostname to detect if DNS64 is in operation. Most 4g modems work as routers exposing an ethernet interface to the host, so it's certainly possible that it's doing 464xlat in the firmware, and if it doesn't tell you on some sort of status page then the only real hint that it's doing it would be a reduced path MTU. I wouldn't be surprised if T-Mobile offer legacy service to any type of business contract or non-phone client though.
  - usr1106 5y ago
    > Most 4g modems work as routers exposing an ethernet interface Not idea about most. I have seen it that way, but our Sierra Wireless requires ModemManager and appears as a wwan network interface.