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What does it mean to install a GSM network via apt-get? If I run this command 2G mobile antennas will grow out of my laptop?
Yes, it's amazing to watch.

But sometimes this doesn't work, then you have to purchase e.g. a supported IP connected femtocell.

There's an old saying: "Beware Software Engineers carrying a screwdriver".

These days it seems to be more true than ever.

Are you having a bad day? May I suggest you remove this comment for your and this comment page's benefit.
My parents told me, "If you don't have anything nice to say, don't say anything at all."

But here I am responding to your comment anyway, sorry mom and dad.

I carved out an exception to that rule, to say something surreal. Have a nice fish.
Interestingly, until now nobody has answered the question what it means. So maybe the linked article is also a joke?
I have a fan now? o.O

At least behave well if you use that name...

Agree, not sure if it was humor or if he was being a jerk.
If you simply don't understand what is implied by this headline it really makes no sense, despite every word making sense.
I've read this three times now, and still can't work out the context. Am I right in understanding he's talking about GSM mobile/cellular networks?
Yes, the project he talks about is OSMOCom, Open Source Mobile Communications. http://osmocom.org/ will give you a little more context. I'm assuming this would allow you to route data over these types of networks given the proper hardware in your own environment.
Thank you for that. This is quite interesting, I thought there were quite strict guidelines about who was allowed to broadcast on 2/3G frequencies? Or is this bandwidth not as controlled as others?
As "extrapickles" pointed out in another comment thread, the spectrum requirement for this is an even bigger hurdle than getting all of the expensive equipment together to pull it off. The tech requires an amount of frequency separation that spreads outside the bounds of the ISM spectrums, so you'd need licensing or would need to be running in a third-world country with no regulations (which is actually a viable use for the tech).

For the unaware, ISM = Industrial, Scientific and Medical. These are the shared unlicensed frequencies that the general public may use. Wifi falls inside of this range.

...or in a place where no one who cares can receive your unauthorised transmissions. If you're not interfering with anyone who has the "right of way" on those frequencies, then you might as well not exist to them.
the cartels in northern mexico have been known to run their own rouge cell networks

http://www.npr.org/2011/12/09/143442365/mexico-busts-drug-ca...

Except by the time you find out you're getting fines.
There are strict guidelines, but generally it is possible to obtain an experimental license for specific events/situations.
I think this is the same software the NOC is using at chaos events to build our local GSM infrastructure. Works pretty flawlessly! I kinda want to see it done using a couple of rad1os or HackRFs though... if that's at all possible...
So, this and a bunch of Raspberry Pis and we can start disrupting the cellular industry?
You'll need to disrupt the ITU/UN bureaucracy first though; or make do with over crowded ISM frequencies for which GSM isn't designed.
Well, disrupting the service they sell by making it useless (until you get caught).
can this be of good use in developing countries?
That was an explicit goal of OpenBTS when I was following it years ago. The GSM vendors want something like $250k per base station, which is unreasonable for third-world or very-rural applications. OpenBTS thinks they can get the radio hardware costs down to a tiny fraction of that to serve low volumes, backed by a Linux box running this software.

Interestingly, their first large-scale field tests were at Burning Man (http://openbts.sourceforge.net/FieldTest/), where there were thousands of active GSM handsets but no cell coverage. They were able to provide limited SMS support between local participants and in later tests allowed some outgoing VoIP calls.

Great,the only concerns I could think of were legal, around ownership of frequency ranges abd interference.
The answer is to work with legal spectrum owners (aka cellular carriers), which is what we (https://fairwaves.co) and other in the space are doing.

Someone mentioned that building a full networks (or even a full base station) is much harder than just apt'ing some software and snapping some cheap SDR. So we spent couple years developing an SDR which is more expensive than your typical hobbyist one (http://umtrx.org) - btw even hardware of the simple version of our SDR is open-source - and then couple years building a base station which complies with all regulations and has open-source in its heart (based on Osmocom obviously). And now we've added a bit of (unfortunately proprietary) glue and we can run fully fledged cellular networks for carriers - mostly in developing countries, as was mentioned before, because demand for simple voice communications is through the roof there. At the same time you can buy one of our stations for your lab and play with it as much as you want (get your test license first though).

So yes, you can't stop progress and technology gets cheaper and more accessible. Which is very exciting.

Any idea what the largest opeb source or non commercial gsm network is?

There must be some widely used ones in developing regions.

The price for BS alone is down below $10k (afaiu, LTE oder Multi-system BS are at $20k). But to run this as a system you need more boxes than the BS only.
Yes, a few examples exist.

[1]: http://www.wired.com/2015/01/diy-cellular-phone-networks-mex...

I doubt that. Building a functional GSM network requires a lot and expensive hardware (antennas, transmitters, amplifiers, relays etc.)
The biggest issue now is legal. GSM requires the uplink to be 45mhz apart from the downlink, which is more than the width of an ISM band.

You can run a european 900mhz GSM basestation in the US 900mhz ISM band, but the handsets that register with the tower will be out of the ISM band.

Sorrrrrrta. GSM the spec requires that 45 mhz of tx/rx spacing by convention, but GSM the technology as we colloquially know it, e.g. if you're code-shifting 2G (i.e. via CDMA) you could get away easily in the 900-928 range @ full duplex. No technical limitation at all there. This was briefly discussed in an older thread by myself and a few other chaps here[1] but I guess tons of other people have had the idea before too haha.

The US spec GSM phones operate at (a nominal) 850 mhz, but like you said there are plenty of eurospec (and asian spec.. and US issued quad-band..) which can operate with off-the-shelf with all the (again, nominal) 900 mhz[2] band tech that's being phased out. It will pick up, negotiate the handshake and route just fine. The issue is really just like any other cellular network: getting tens of thousands of antennas up, and having people buy new phones that are quad-band and/or carrying around an eBay phone for what amounts to a novelty.

I'm not on the cutting edge of milliwave or RF anything (all voodoo to me) but as I see Agilent come out with more and more sensitive test gear, I can only presume that the wireless industry is getting way better at tuning YIG's, VXCO's, eliminating side-band tone bleed, and what not. Much like the analog (i.e. 1g, remember those Motorola flip-phones? I do1!) -> 2g shift increased capacity by 3x, I'd have to imagine new encoding techniques and what not are being developed by the PhD's and postdocs. Who else is going to buy a $300k network analyzer otherwise, haha

[1] https://news.ycombinator.com/item?id=11414069

[2] If you talk to old-time HAMs they'll joke about how the FCC really regrets throwing away a few hundred billion dollars worth of band in that spectra alone. You can pack a lot of content into each Hz down down there.

Could you clarify a couple of acronyms - YIGs, VXCOs?

Also isn't the real viability issue with this the MSC? Once you've registered with a base station you need to backhaul it to a switch that's capable of routing the call to another hand set. Maybe there are some good affordable options now for a soft swtich that also provides HLR/VLR capabilities? A real class 5 switch like those made by Metswtich are hundreds of thousands of dollars I believe.

A search for "tuning yig" led me to this: https://en.wikipedia.org/wiki/Yttrium_iron_garnet
VCXO = voltage-controlled crystal oscillator
Good point. Doing that would require at least a firmware change on the handset as I suspect the baseband code is built around the ARFCN (Arbitrary Radio Frequency Channel Number) which enforses that separation. It probably wouldn't be that hard to change the ARFCN formula on a handset, though the easy way would make it not compatible with regular networks.
Why would the handsets registering be out of the the ISM band? What if you bought a quad band phone, wouldn't that work?
The handset would be transmitting at 880mhz, the tower at 925mhz. The ISM band is 900-928, making the tower good, but the hadset not.
The cost is down into hobbyist range. Not the cheapest hobby, but not a big deal for a lot of people. Look up USRP, HackRF, and BladeRf. I think BladeRf is the cheapest at $420.00 USD.
Putting up a single, limited range BTS is not the same as full scale, functional GSM network. It's similar as creating your home network with OpenWRT flashed router and calling it Internet.
Do does that mean everyone can put up develop their own Stingray now?
No. For that, you'll want [0] (on HN a few days ago). This is mostly for making it easier to run your own legitimate GSM network, and of course the software has been available for a long time, it's just now available via the Debian repositories.

[0]: https://www.evilsocket.net/2016/03/31/how-to-build-your-own-...

Is there any way to use this software to implement a network-connected femtocell cheaper than the ones AT&T, etc sell?
Where's some good reading (general GSM stuff, etc) to do to be able to use this in a meaningful way?

I'm kind of interested in the idea of setting up a phone network for Nowhere (and other burner events, where often there's no actual phone signal at all), but it's a whole area I'm completely unfamiliar with.

Is it https://en.wikipedia.org/wiki/Cell_on_wheels
No, that (COW) is a combined radio station, power supply, and equipment for connecting to ground based backhaul networks. This release is only software.
It's just apt now.