AweSIM and VoLTE status

Interesting. I thought before it relied either on the T-Mobile or the AT&T networks, but that webpage only lists AT&T (at least currently). Of the two networks, it was my understanding that T-Mobile was the one that cared less about what device you used on their network.

I did more reading on old posts, and T-Mobile definitely had been an option for a network backbone. Apparently Purism gave up on using T-Mobile as a backbone network and is only focusing on using AT&T. That is confusing, however, as it seems that AT&T has shut down its 2G and 3G, leaving only 4G as an option for the Librem 5. Calling on 4G requires VoLTE, so…I can only assume Purism has worked with their AweSIM subscribers to enable VoLTE on the L5 modem and it’s working on the AT&T network? It would be really cool if someone that is not employed by Purism could confirm this.

Not until Feb. 22…unless:


Interesting; thank you for sharing. I guess we will find out for sure on Wednesday if AT&T’s 3G got shut down.

After Kyle Rankin confirmed in the other thread that VoLTE was working for him with his AweSIM service, I decided to see if I could get it working with AT&T directly (being as their plan is $70 cheaper for the plan that fulfilled my needs). After promptly receiving the SIM from AT&T, I put it in my Librem 5 and was surprised to see it seemingly successfully connect to and register with AT&T’s network. I even saw 4G in the wireless signal portion of the screen. To my further surprised, calls worked too…but only on 3G. Apparently AT&T’s claim that they shut down their 3G network on Tuesday was not completely true, as I was able to make and receive calls on the 3G network. That said, 3G is being killed, so I attempted to get VoLTE working by running the commands that are supposed to enable VoLTE for my Librem 5’s BM818 modem. Unfortunately, calls were still not going over VoLTE. I then spent at least an hour on the phone with AT&T, going back and forth with the representatives. At the end of it, I think they may have killed my AT&T 4G data, as my Librem 5 stopped being able to use data when only 4G was enabled. The AT&T representatives claimed that my phone is incompatible with AT&T’s network, which means either: one, the AT&T representatives are incompetent and are only reading off what they see on webpages about compatibility (quite likely), or two, Purism’s AweSIM service actually won’t really work on AT&T’s network, either (which is also possible, although I would like to think that maybe Purism could fight AT&T better than I could to get 4G and VoLTE working).

All that being said…I’m probably going to kill my prepaid plan with AT&T. I now have the choice of trying T-Mobile (or an MVNO running on T-Mobile’s network) or trying the AweSIM service (which is stupid expensive for what I need).

If VoLTE doesn’t work on T-Mobile’s network, an AweSIM subscription may literally be the only way to have VoLTE voice calling on the Librem 5 in the USA (assuming Purism can actually get and/or keep their MVNO service working on AT&T’s network).

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Did you mean “not going over VoLTE?”

I wonder if the 3G calling was a case of implementing roaming over T-mobile… See: (The paragraph that begins “In 2011.”

Of course, maybe AT&T really hasn’t completed shutting down 3G. It sucks to be in the dark about all this stuff.

Unsurprising, given their whitelist/IMEI check.

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Correct, I mistyped and meant it was not going over VoLTE.

If AT&T has a whitelist that they enforce, how does Purism’s MVNO get the same model of modem to work on AT&T’s network? Purism can’t do magic; they are using the AT&T network, so it has to be allowed on AT&T’s network or it won’t work.

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I wonder if Purism, being a MVNO, has bargaining power with AT&T that the Average Joe does not have. For example, Purism tells AT&T they will be a MVNO on their platform (which I assume entails some fiscal benefit for AT&T, probably from Purism), but only if AT&T allows them to have certain modem models (e.g. the BM818) be allowed on the network. Thus, AT&T has a whitelist that they will allow a bunch of approved devices on, but they can manually make exceptions for IMEIs that Purism has on its AweSIM MVNO. The benefit for AT&T is presumably monetary compensation; the benefit for Purism is they can offer a wireless service in the USA that the Librem 5 actually works on.

I think I’m still going to try a cheap T-Mobile prepaid plan before trying AweSIM for $100/month, but I’m less and less hopeful for the Librem 5 will be usable by anyone other than tech nerds with a bunch of extra money laying around.


Just made my first voice call on 4G (LTE AT&T Network) using Purism awesim on an L5 with US modem. I also received a call and while the ringing is laggy, the call quality is excellent and i and the other person heard the ringing. Plus it did not drop to 3G neither has the modem or connection dropped out at all last hour testing it.

It took a while to get the correct awesim activated since my account had tons of dupes for some reason but with help from purism support they worked it out, couldnt be happier.

Honestly i have no idea what would be different technically between 3G voice and 4G voice, i assume both use a digital signal and connection not analogue, and wouldnt that by definition make it VOIP wouldnt that even include 1G, 2G?


Yes but 4G can use superior codecs. So it is possible that you will notice better voice quality on 4G as compared with 3G. Whether it actually is using a better codec, well I don’t know how to check that on the Librem 5 and it might be hidden from the phone and only known inside the modem, and whether you would notice it anyway are open questions.

Maybe but that in and of itself would undermine the idea that you can (very theoretically at this stage) take out the existing M.2 modem card and put a random M.2 modem card in, where you yourself could in theory have written the necessary interface code to run in the Librem 5.

True freedom to replace and/or upgrade as you see fit would mean that the whitelist is thrown away.

I have no idea what reality is.

I have less experience with traditional digital audio, but my understanding that digital audio is not technically Voice over IP, although VoIP is digital communication.

It is my understanding that all cellular modems are black boxes at some level, so even the theoretical freedom described is never truly attainable in today’s cellular environment (even if there was a genius would could code all of that himself).

interesting point i think to clearify these discussions wouldnt it be better to discuss what codecs are used, supported, amd i know 4G has encryption and 3G does not, who owns the keys etc, if voice and data can use the same basic internet protocols or ride on them then the network provider wouldnt be all that much wiser what you are using the phone for (assuming it is encrypted and you have the keys).

A way to circumvent the whole blocking you can just tell the provider its a hotspot device that typically has worked for me in the past (also means no voice using tradition service though).

That’s right. In the way that most people use the term VoIP, a voice call with your MVNO/MNO is different from VoIP.


isn’t really right.

If you are genuinely using VoIP (over a mobile network) and you are using encryption then your MVNO/MNO has not much idea * what you are using the phone for, not much idea * what codec you are using, no idea what you are saying. Your MVNO/MNO does not have the keys needed to get involved with your VoIP call.

*Obviously your mobile provider sees what IP address and port you are communicating with, so if that’s on port 5061, and your mobile provider sees the average bandwidth that you are sending to that IP address, then the provider can make reasonable guesses.

On the other hand, if you are using a voice call (whether over 3G or 4G) then encryption is not relevant to your mobile provider - because the encryption endpoint is your MVNO/MNO and hence they have the keys and they know everything about the call - codec, content, …


Unfortunately, my L5 USA has been totally unusable on T-mobile. This is even after getting a different modem shipped to me. (And yes, I’ve been communicating with tech support on this, but it has been 2 weeks since the last contact.)

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I too tried T-Mobile and was unsuccessful with getting VoLTE working. Purism released the SIMple service plan, which is cheap enough for me to justify paying for it because the vast majority of my life is in trusted WiFi range), and that works, so I now have a usable Librem 5 (which is cool). That being said, the whole “Purism devices allow for freedom!” notion is a bit nonsense in my opinion. At least currently, you are free to have a Librem 5 that is a pocket computer in a smartphone form factor, but if you want to have a Librem 5 that actually operates as a phone, the only guaranteed way to do that is by buying your cellular service through Purism. Your freedom is constrained by its functionality (or lack there of) on cellular service plans other than Purism’s MVNO.


Its ironic that our quest for digital freedom has simply lead to the transfer of our dependency from one ecosystem to another. Still, I’d rather overpay for my privacy respecting AweSIM service than give it to AT&T.

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Maybe I’m getting old, but the more I’ve thought about it, the more freedom looks like using less technology in general. Don’t have to worry about texts being snooped on if you go to the lake with your friend and have a real conversation in real life. Obviously I haven’t followed this to it’s logical conclusion (as I have a Librem 5 and several other computers and computing devices), but that’s what freedom is looking like more and more.


One L5 user, at least, is having a different experience with an MVNO on AT&T’s network:

I assume this sentence is qualified by “in the US”. (I tested two of the three MNOs in my country and both of them worked out-of-the-box with the Librem 5. I don’t have a suitable SIM for the third MNO.)

So it seems as if all this whitelisting / IMEI checking BS may be country-specific. That in turn suggests that the problem may be political, not technical. That is, you need to bust the balls of your Congress-critter to make this kind of restrictive practice illegal.

If you can fight for your right to repair then you can fight for your right to use the phone of your choice.

Just make sure you don’t take your phones with you. Or if you take a Librem 5, use the HKS to kill the microphone. Even without any phones, so many places are under camera surveillance. So a lake is probably a good choice.

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