You are making/receiving the calls with Gnome Calls?
I have a JMP phone number. When I setup Chats with the JMP account as XMPP, I get texts to the JMP number.
I get “Account encountered an error” when entering or trying to use JMP via a VOIP account with Calls. 
The transport defaults to UDP and the Port to 0. Maybe it should be something else?
I know that port is wrong.
So I couldn’t tell from the replies here, whether or not your own personal SIP service should work within STIR/SHAKEN (once it has been fully implemented) or not.
XMPP client port is 5222 and sip is 5060.
So I figured…
OK, bear in mind that I am using Gnome Calls here.
So I tried 5222 and got: Account is offline; domain could not be resolved.
Then I changed the Transport to TCP and got: Account is offline
Later, without doing anything further, I got: Account encountered an error; Internal error occurred.
Progress, I think.
It’s been pretty quiet on the VOIP front, so I would give a short personal update. I installed Gajim and entered a login to my JMP/Cheogram account. It connected on port 5222.
GOOD: I can send/receive messages to other XMPP users… and seemlessly send/receive SMS to mobile phones by adding them contact as “+1<phone#>@cheogram.com”.
ALMOST GOOD: I can make/take voice calls to both XMPP and telephone calls. I can hear the other party 5x5, but they cannot hear me.
TO DO: Test video calls and file transfer.
INTERESTING: I can open Calls, call the phone number associated with my XMPP account and the call loops back to ring Gajim. When I answer, it connects, but of course there is no feedback – because Gajim never patches the mic!
Anyone have experience Gajim?
How about any service other than Giigle Voice?
I wanted to let everybody now that I ordered and received a JMP.chat physical SIM. It works very well. I do not use it as my main cellular provider (I use Mint-Mobile) on the Librem 5. However, my experiments with it show the sim for JMP.chat to be very reliable.
This is cool because I can have WIFI calling and Cellular calling all on one number with JMP.chat.
You can even add multiple JMP numbers to your account (with additional subscription costs), and have them all on one device (and on all your devices). It’s a cool service.
You will have to report back if it continues to work without bugs, because that is very tempting 
I’m using JMP.chat plus their data SIM (or an alternate data-only roaming SIM) as my main mobile “carrier” now. (Not yet on the Librem 5, though; I’m still using degoogled Android.)
Calling works seamlessly over the internet with no need for VoLTE, using either the native Android dialer or their Cheogram app (available from F-Droid). (Other XMPP clients can work as well.)
“SMS” and “MMS” (including group messages) are handled by the Cheogram (or other XMPP) app.
Unless I delete chat histories, my messages follow me to whichever alternate phone or computer I want to use.
JMP can’t call the short-code emergency services, but the phone itself can, even without a SIM card. However, emergency services can’t see a call-back number for you, so that’s something to be aware of.
P.S. I don’t know if all the kinks have been worked out to use XMPP like this with the Librem 5, but if not, it’s probably close to operational with the right XMPP application.
P.P.S. As stated elsewhere, JMP only provides Canada or U.S. phone numbers (new or ported in), but calls and messaging will continue to work as normal no matter where in the world you travel, as long as you have an internet connection.
Another advantage of using a roaming data SIM in conjunction with XMPP and/or SIP is that the SIM often can use more than one national network to provide service. For instance, in the U.S., the data SIM can connect to either T-mobile or AT&T, dependent on which one has available coverage in a particular area, thus bypassing AT&T’s restrictive device “whitelisting,” because it’s a data-only SIM. And obviously not requiring VoLTE to work, as I mentioned above.
Of course, you can also use XMPP or SIP in conjunction with a regular mobile SIM, and have both the phone number from the service provider, and an additional phone number or numbers from, e.g., JMP or a VOIP provider.
Add a dual SIM phone into the mix, and you can expand your options.
Do you still like linphone for SIP?
Also, is it independent of the native SIP support in android that got dumped from android a few major versions back? (That is, does SIP work in linphone on android 16?)
I haven’t used SIP in quite some time, but I’m pretty sure Linphone still works on Android, regardless of the removal of native Android UI for SIP.
As usual, you are correct.
I have three Android phones, all with Mint Mobile service. Each phone has its own number via the Mint Mobile SIM on each phone. I haven’t even memorized those numbers. After setting everything up, I never need to know those numbers. To unify all calls and text messaging for all three phones under one phone number, I use Google voice. Yes, I hate Google and am under no illusions, thinking that I have privacy. But GV makes everything convenient and there are no equivalent services out there that I know of.
So a member of my family recently had a medical emergency at 3:00 AM one morning. I had to call for an ambulance to take her to the hospital emergency room. So I called 911. Fortunately, the medical emergency turned out to be not that bad. Four hours later we were back home with minimal repercussions.
But when the 911 operator was on the line I senced some stress in the operator’s voice. I had registered my GV phone number with the 911 system previously. They still went quickly from a helpful voice to what seemed almost like interrogators. “What number are you calling from" the guy said sternly. I gave them the GV phone number. The operator said “well that is not what I see. I see a number of (the phone’s real number per the SIM card)”. That is not how I have GV set up. He should have seen the GV number as everyone else sees when I call them. If he has special equipment that shows him my phone’s number per the SIM card despite my efforts to display the number that I want him to see, that’s his problem, not mine. He said sternly “where are you calling from?”. I said (somewhat bothered) back “look, I have Google Voice on my phone. You should see that number and I have it registered with the 911 system. Something must be wrong with your equipment. Let me give you my current location”. Then I gave him my home address.
When you’re using a Voip phone, a lot of official places like 911, banks, and some others think they can be cute and see information about your setup that is different than what the system you are using intends them to see. Then they assume that the mismatch in information is your problem. I figure that that is their problem, not mine. But in reality, the problem is actually my problem, not theirs. I have to break my usual protocols and give them a number that I block and don’t answer, if I want in to my bank account or whatever I am doing. That pisses me off. But there’s nothing you can do about it. In the case of 911, I don’t know what I would have said if my non-mainstream SIP solution was so complex that I knew that the 911 operator wouldn’t have understood my explanation. They treated me almost like a criminal as it was, just for using Google Voice. We need something that can spoof the phone’s real number from a SIM level. Otherwise there will always be someone out there that assumes that you are doing something illegal if you use a SIP service. And often the problem is that the idiot on the other end that suspects you’re doing something wrong, doesn’t even know what a SIP service is. And it’s difficult to explain how a SIP service works in the middle of an emergency.
If the government would require implementation of the STIR/SHAKEN protocols right away, things would go so much easier.
For what it’s worth I was a GrandCentral user years before they were acquired by Google. Wasn’t thrilled with the acquisition, but kept on with it under the Google Voice banner.
Once the Snowden revelations broke and I learned about the PRISM program, I realized I was a fool for ever trusting these companies with my data. I decided I was done with Google, Yahoo et al and closed all of my accounts with them. Ported my Google Voice number to voip.ms to ‘roll my own’ and never looked back.
Since then I have registered the DID I use for the home VoIP ‘land line’ with their E911 services. Never had an issue dialing 911 with it. Dispatch can correctly see the number and registered address.
Not sure if this changes when you’re using a VoIP DID on a mobile device.