I’d be delighted to see mesh networks get further development, but don’t forget that they have some inherent weaknesses.
1. They can’t jump gaps wider than the limited range of WiFi. They will work inside a city but not between cities. That allows the government to move against protests city by city. Use the army to crush one city then move on to the next.
2. All that hopping around looking for connections is wasteful. For A to reach B, hundreds of active links may be required. That’s fine if A only needs to talk with B. But in the real world, with most means of communication shut down, everyone in the mesh will be messaging constantly, particularly when the message they sent a friend across town doesn’t get an immediate response like it does with their cell phone. That’s why large two-way radio networks typically have a net control and why net discipline is so important.
3. Following up on #2, an Open Mesh’s very openness would make it easy to jam. The government would only need to seed the city with its own innocent-appearing open messaging devices, which would generate excessive traffic (jamming up the system like the USSR did Radio Free Europe), create bogus messages, (confusing protest leaders), or serve as a message black hole, claiming to have received and passed on a message but actually trashing it. There are techniques to deal with those problems, but those techniques have to be prepared in advance. In a repressive society, that’s not easy to do.
Finally, don’t forget that in many situations the communications link that matters most is the flow out of the country to draw international support. Long distance telephone calls leaving a country is usually easier to shut down than Internet is within a country, so it can almost be assumed that a threatened regime would do that. Sat phones would work, but they’re so expensive, it’s unlikely there would be many of them. I also suspect that repressive governments, concerned about spies, already have the technology to locate sat phones.
One option I’ve yet to see written about is amateur radio, particularly using a digital technique called PSK31 (described on Wikipedia). Low-power transceivers for PSK31 can be homemade inexpensively. The digital processing to turn a signal into data can run on a PC or laptop and even smart phones. Messages can be prepared in advance and sent very quickly, at about 50 wpm. And the signal processing techniques mean that even a weak signal can be copied.
Finally, because you’re dealing with trained radio operators (not a chat-crazy mob), much of the confusion that an open mesh generates isn’t a problem. For messages from the leadership to the rank and file, messages could travel outside the country via a means like amateur radio. They could then be broadcast back into the country either openly (for mass protests) or using a prearranged code (for smaller groups), like that the BBC used for resistance groups during WWII.
Of course, access to powerful broadcasting stations often requires the support of governments outside the country, something that’s been distinctly lacking when the repressive regimes are in either the oil-rich Middle East or impoverished Africa.
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