Most posters here seem not to have read the details on the Github page, and are missing the point.
This is a way to have encrypted point-to-point communication or (in some cases) network using any radio (or other) transmission equipment that will transmit/receive audio signals and allow you to tap-into the analog audio circuit of the transmitter and receiver. You could use it with:
- telephones (landline kind)
- mobile phones
- radio transceivers (legal or illegal - the protocol doesn't *require* that you break the law!)
- optical communication equipment - free air/fibre
- etc. etc. etc.
It just defines a common protocol and means of modulation/demodulation.
They take a whole lot of words to say this, and throw in a lot of revolutionary rhetoric.
And yes, it's very similar to amateur packet radio, except encrypted. So, lots of existing code to draw from.
It's well within the capability of any PC or smartphone today. Although I let my ham license lapse many years ago, I do have a couple of receivers squirreled away somewhere, and a few years ago I experimented with listening-in on amateur packet radio. You just run the output from your receiver into the input of a Soundblaster card (I SAID this was a few years ago...) and the application handles the decoding.
An interesting side-note: If you're near an airport, you can use similar software to decode VHF ACARS transmissions. (The kind that hasn't helped much in locating MH370). Just install some open-source software, hook your scanner up to your PC, tune to the right frequency, and it turns the squawks into somewhat-readable messages.
It's biggest drawback is it's biggest strength, IMO. It DOESN'T define a common frequency, some complex frequency-hopping or spread-spectrum scheme, or even common transmission media. It would be extremely hard for it to gain critical mass. On the other hand, it means there are an awful lot of places one would have to look to find it. It's up to whatever group that wants to communicate to settle on a transmission media and (if applicable) frequency.