I am tired of paying for roaming, of being location tracked by my provider and running out of SIM slots.
So I have decided to connect some SIM capabilities to my server and set it up as a sort of proxy that I could access over the internet to send regular SMS and make regular calls through the server.
As far as I can tell it seems to be really complicated to do in linux and I just couldn’t find anyway that would actually support sound over calls.
The only solutions I found right now are to get an old phone (not ideal because of the price, battery and reliability) or use something like
https://www.makerfabs.com/maduino-zero-4g-lte-sim7600.html
Which can be connected to the server on the aux and serial ports. This is not too pricey but still seems like a bit much for my needs.
My question is, are there better ways? Really all I need is SMS and calls.
What you need is a sip server / interface for making VoIP call through internet, there are many implementations and servers, selfhosted and paid. Pick up one you like.
Please, be aware that the quality of the voice call depends and a lot of the data rate. Keep this in mind uif you are in remote locations with poor coverage.
It is always recommended the asterisk + the freepbx for the gui. Please be aware that I don’t have experience with those systems
Please, be aware that the quality of the voice call depends and a lot of the data rate. Keep this in mind uif you are in remote locations with poor coverage.
Nowadays most cell calls are VoIP anyhow. Heck in the US they shut off the old networks and only allow VoLTE/Vo5G
Yea, buts that very different than software VOIP.
I know this first hand by having VOIP-only voice on my phone via a service using Monocles Chat or Cheogram.
Voice calls via my cell plan are much better quality and more consistent than VOIP via an app. I suspect this is because voice calls over 4G/5G are encoded by hardware.
Even Google Voice for calls is pretty awful, which is why I’ve never paid to use it for voice calls.
I suspect what you are looking for is a gsm gateway. There are many standalone implementations, some ready made, some a bit more DIY
I tried looking for that, all I found were pricey enterprise level stuff, small ones that only support 2g (dying protocol), and ones that have a cloud service and not self-hosted. Do you know of anything else?
The problem is that if you want to offload SMS and voice, you’re going to be using data to do it. Whatever roaming fees will probably still apply.
I have wifi, I don’t need data
In that case, just use VPN software like Wireguard. You can reroute everything through your home setup.
So you’re looking for a self hosted VoIP and SMS solution. Google voice does let you send SMS over Wi-Fi, but it’s not self hosted.
For SMS KDE connect + VPN into your home network should work. Remote calls is a tough one tho.
https://silent.link/. Maybe?
The only way to connect the SIM number directly is to hack the VoWiFi protocol, but this is not trivial and you still need to install the SIM in the server.
Option 2 - Buy a home SIP2GSM gateway. But it’s quite expensive (by the standards of my region anyway). SMS work with SMPP, calls work too. For goIP I wrote telegram SMS gateway if you interesting: https://github.com/lifespirit/telegram-smpp-bot
Or use SIP providers from your region/operators that support SIP connectivity and then enable full calls redirection. For calls ok.
UPD: or just use VoWiFi from mobile phone. But you need sim slot in phone.
Anyway in all another way you need install asterisk/freeswitch and write config fot it. And linphone client.
