31–37 of 37 posts
Earlier quoted context omitted.
Binary blobs embedded in hardware are acceptable from a free software standpoint. As long as they can't be remotely updated.
Almost all wireless modems can be remotely updated. So this phone is mostly running proprietary software. That will be the case for any cellular technology for the foreseeable future.
I made my own cellphone once by purchasing the battery separately.
But this is a much more advanced project - you need to supply your own box to put it in too ..
Earlier quoted context omitted.
Almost all wireless modems can be remotely updated. So this phone is mostly running proprietary software. That will be the case for any cellular technology for the foreseeable future.
There is an open source implementation of GSM baseband software http://bb.osmocom.org/trac/ . Very limited hardware support though.
I don't think most people will find this helpful though. One of the main problems is that the chip vendors don't tend to release the hardware specifications and development tools.
Several of the USA carriers are itching to phase out all their 2G networks, so that they can re-use that spectrum for LTE. So a 2G baseband has limited usefulness moving forward.
Adding to that, implementing any kind of 3G (WCDMA, HSPA) is an order of magnitude more complex. Just the handoffs between a 2G and 3G cell tower are complex.
Sadly, LTE is sort of simpler than the 3G technologies, because its all just data (no special transfer mode just for voice). However, instead just going all IP protocols for voice and other services, they decided to implement a host of new and complex protocols for Voice-over-LTE (VoLTE). And some of the current chipsets now have to handle handoffs between LTE, 3G and 2G.
So this open-source stack will not get carrier approval. And even if it were to get popular, the FCC would likely throw up a stink, and the carriers would start banning users that are using a non-approved 2G stack. They would be somewhat justified in that because the existing baseband implementations go through extensive (and expensive) compatibility testing to make sure they place nice with the network under all possible conditions.
If you want to do open-source radio, your first fight is to get some spectrum that can be used unlicensed. There's big competition for the best frequencies (that can carry enough data and have decent range), so the spectrum auctions cost billions of dollars, and the winners are the existing major players.
Only one question -- can you take this on a plane? A while ago I had a cell phone where the battery charging circuitry went out. The battery was 3.6v, so I hooked up (via Velcro) a AAA battery holder and used rechargable NiMH batteries. However I was told (when I called the airline I was traveling) that it most likely wouldn't make it past TSA.
Earlier quoted context omitted.
There is an open source implementation of GSM baseband software http://bb.osmocom.org/trac/ . Very limited hardware support though.
Huh, that's interesting, I hadn't heard about that before. I don't think most people will find this helpful though. One of the main problems is that the chip vendors don't tend to release the hardware specifications and development tools. Several of the USA carriers are itching to phase out all their 2G networks, so that they can re-use that spectrum for LTE. So a 2G baseband has limited usefulness moving forward. Ad…
Cool ... this gives me hope for the future I want. The day will come when we will all hold cell phone shaped PCs. You'll be able to interact with them as you do now. However, when placed within 10 feet of a keyboard or mouse, they'll automatically (configurable) and wirelessly use those peripherals ... keyboard and monitors on the fly baby! Imagine optional super thin foldable displays to pack in the bag ... keyboard…
Earlier quoted context omitted.
Huh, that's interesting, I hadn't heard about that before. I don't think most people will find this helpful though. One of the main problems is that the chip vendors don't tend to release the hardware specifications and development tools. Several of the USA carriers are itching to phase out all their 2G networks, so that they can re-use that spectrum for LTE. So a 2G baseband has limited usefulness moving forward. Ad…
So it sounds like there's little chance of a truly open source cellphone. What a shame. I wonder what the privacy implications are of having a remotely-updatable module inside every phone. Can carriers break encryption this way? Or otherwise snoop on users?
Yes they can snoop on the users, but they can do that now, without any changes to the radio firmware on the phone. The modem can't really do anything without the carrier's network.
If you mean spying on users by surreptitiously turning on the microphone, that's something where you want to control the phone's application processor rather than the modem firmware. Mostly because modern phone architectures have the microphones connected to the app processor instead of directly to the modem as in the feature-phone days (like a few years ago). Modern phones have sophisticated echo and noise reduction and use multiple microphones for that. And the audio is now used for other applications (like Skype or video recording) so it makes sense to hook up the microphones to the app processor instead.