I have a theory on why none of the Librem 5 developers have been able to get SIP service working on the Librem 5. I could be wrong but my theory seems to make the most sense. The combined intelligence and software development experience between everyone who is doing development work on the Librem 5 seems to be way too high for them as a group, to lack the needed programming skills. These guys (and maybe some women) are too good at what they do to simply not be capable of fixing broken code. They have the source code to work with. They do not lack the required programming experience and knowledge of code writing. The SIP service should work, if not one other unresolved problem. And that problem is a big one.
I purchased a Grandstream device and was able to get it working. This is a small box that plugs in to both your landline phone and into your router. You have to subscribe to a SIP service to make it work. The SIP service charges you around $2.00 per month for your phone number, and one penny per minute. You have to configure it. But once it works, it’s a landline phone that connects to the PSTN via the internet. When you pick up the handset, you hear an old fashioned dialtone. It’s reliable and works for the users, the same as any landline.
But here is the catch. Configuring that Grandstream box is like configuring a router, except much more difficult. There are well over 100 fields in the settings, maybe 200 or more settings. I didn’t count them. Some of these fields have to be filled-in perfectly. If you fill in everything correctly except you do not have one critical field filled in correctly, then everything fails. You don’t even get a dialtone. Your phone does not work. Every required field has to be filled in correctly. Some fields do not matter. But no one tells you which fields are required and which ones should be left blank. And most of those fields do not have a descriptive name that most people would understand. Even if you were to understand the purpose of most of those fields (which I didn’t), you wouldn’t have the answer as to what to type in. The odds of finding all of the required information and getting it all filled-in correctly are very close to zero. To make things worse, you have to set up your SIP account on your SIP provider’s web login for your account, once again, perfectly. Some fields there you can leave blank. Some fields require perfect information. You don’t know which fields are importand and which fields can be left blank. Once again, there are hundreds of fields that could be filled in. Many of them, you won’t have a clue about what to enter in to that field. To make things even more difficult, how you setup the device depends partially on how you configured your SIP account settings. Everything has to work together. One mistake anywhere and nothing works. My SIP provider spent two hours with me, walking me through every field in both my device settings for the Grandstream box (a popular piece of hardware), and in my login to my SIP account. They knew exactly what was going on and I quickly typed in what they told me to type in, at each and every field that mattered. How many Librem 5 developers know that much about SIP communications?
The Gnome dialer has something like four fields that need to be filled-in for the SIP settings. What about the remaining 100+ fields that aren’t even visible to the users? Well, they are all blank or have at least one and maybe several dozen critical errors in them, wherever they exist. They’re all hidden either in the source code or are in some configuration file that no one knows about. The Librem 5 software developers are code writers, not SIP Engineers. They probably do not know how to come up with or to enter those values in to the software for the Gnome dialer, any better than I knew how to configure my Grandstream device. A real SIP Engineer could probably sit down with a Librem 5 Gnome dialer developer and associated code, and just make it work. Once it works there, then Purism can make it work everywhere.
Right now for SIP on the Gnome dialer, it’s like hiring a plumber to install your electrical outlets. People make guesses, take some shots into the dark, then it fails, and that plumber just gives up. A qualified person needs to address the problem. The Librem 5 software developers need to admit to themselves that they lack the necessary skills and experience to fix this specific problem with the Gnome dialer. They need to find an expert in the field to work with them. Anything less is just pride, blocking the way to progress. As an Electrical Engineer myself, I had no problem telling the hourly worker at my SIP company, that I didn’t understand most of the settings for my device. He quickly solved my problem.