Considering that OpenBSD’s umb(4) and umsm(4) drivers support cards like the Quectel EC25, which comes in a USB variant, I was wondering if it was (at least in theory) possible to make calls using OpenBSD. I know you can get to the internet and send SMS with the smstools port, but what about calling ?
You can with SIP. The only thing is that you need a SIP server to hold your number. As far as i know moder telephony is internet telephony. SIP servers establish connection between 2 clients. SIP servers hold a database with phone numbers, when you call someone you ask which is the current ip for a given number. SIP servers are the ones that mantain the link between a phone number and an ip (beyond other link related stuff).
Without a global server that holds a number phone for your current ip you wont be able to get calls or even make it.
But you can create a SIP server for your friends probably. That’s how the FSF has it setup.
I doubt OP meant SIP. They likely meant literal telephony.
Google search yields some threads about people doing this or trying to do this. So likely yes.
Yeah exactly. What I meant is actually interfacing the umb/umsm device to make calls.
I can’t find anything on Google. Can you share what you found?
Sorry, I’m a total noob in actual telephony, so can’t evaluate how good those results are.
It just seems that such functionality is supported for the device, and then you probably can do everything via AT commands.
Though it looks like some additional board is required? I don’t know.
Some manual - https://www.manualslib.com/manual/1511434/Quectel-Ec25.html?page=91
Something in Russian, though VoLTE may not be what’s needed (but the general idea may be clear enough with Google Translate) - https://habr.com/ru/articles/696042/ .