[no_carrier]

Here in Australia, POTS lines have been completely decommissioned, UK will be switched off by end of 2025 and I'm assuming there's similar timelines in lots of other countries.

[vladvasiliu]

They're on the way out in France, too. New buildings don't get copper anymore, only fiber.

However, as I understand it, at least for commercial use, the phone company provides some kind of box that has battery-backing so it can provide phone service for a certain duration in case of emergency.

[tonyarkles]

The tricky part with that is that, at least in Canada, the RJ11 ports on the ONT are generally VoIP. They provide the appropriate voltages for a conventional POTS phone to work but digitize & compress the audio and send it along to the Telco as SIP or whatever. That works fine for voice but you're probably going to have a hard time using a conventional POTS modem over that connection. I've never tested it and am honestly pretty curious to see how well/poorly it would work.

[hujun]

now there are LTE modems

[jethro_tell]

If you are the lte network, it gets a little tough to do oob that way, especially if you’re basically a monopoly in many service areas.