Communication Tools to Help Dissidents

Activists in Cario's Tahrir Square "share the power" (via cairofeb6_036)

Outlining some handy technological communication tools that can be put to good use in by-passing authoritarian regime's crackdowns on communication, this article by The Economist is definitely worth reading in full, below is an abridgment:

With a tin can, some copper wire and a few dollars’ worth of nuts, bolts and other hardware, a do-it-yourselfer can build a makeshift directional antenna. A mobile phone, souped-up with such an antenna, can talk to a network tower that is dozens of kilometres beyond its normal range (about 5km, or 3 miles). ....

... [homemade antennae's] existence has recently been valuable to the operation of several groups of revolutionaries in Egypt, Libya and elsewhere. To get round government shutdowns of internet and mobile-phone networks, resourceful dissidents have used such makeshift antennae to link their computers and handsets to more orthodox transmission equipment in neighbouring countries.

... after Egypt switched off its internet in January some activists brought laptops to places like Tahrir Square in Cairo to collect, via short-range wireless links, demonstrators’ video recordings and other electronic messages. These activists then broadcast the material to the outside world using range-extending antennae.

... Directional antennae, unlike the omnidirectional sort, transmit on a narrow beam. This makes it hard for eavesdroppers to notice a signal is there.

Another way of confounding the authorities is to build portable FM radio stations. ... Though these stations have a range of only a few kilometres, that is enough for the leaders of a protest to use them to co-ordinate their followers. The stations’ operators act as clearing houses for text messages, reading important ones over the air for everyone to hear.

...[a group called Access] is equipping a network of ham-radio operators with special modems that convert digital computer data into analogue radio signals that their equipment can cope with. These signals are then broadcast from operator to operator until they reach a network member in an area where the internet functions. This operator reconverts the signal into computer-readable data and then e-mails or posts the information online.

Satellites provide yet another way of getting online, though they are expensive to connect to. It is, however, beyond the authorities in most places to shut down a satellite operated by a foreign company or country. The best they can do is try to locate live satellite links using radiation-detection kit similar to that supposedly employed in Britain to seek out unlicensed televisions. The result is a game of cat and mouse between the authorities and satellite-using dissidents. Tactical Tech, for example, has trained dissidents in five countries to rig satellite dishes to computers in order to get online. It advises some users to log on only for short sessions, and to do so from a moving vehicle.

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