Signaling Dissent: Unorthodox Links to the Internet

Via economist.com -

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). As Gregory Rehm, the author of an online assembly guide for such things, puts it, homemade antennae are “as cool as the other side of the pillow on a hot night”. Of late, however, such antennae have proved much more than simply cool.

According to Jeff Moss, a communications adviser to America’s Department of Homeland Security, their 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.

Technologies that transmit data under the noses of repressive authorities in this way are spreading like wildfire among pro-democracy groups, says Mr Moss. For example, 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.

According to Bobby Soriano, an instructor at the Philippine branch of Tactical Tech, a British organisation that teaches communication techniques to dissidents in five countries, such antennae can even foil government eavesdropping and jamming efforts. Directional antennae, unlike the omnidirectional sort, transmit on a narrow beam. This makes it hard for eavesdroppers to notice a signal is there.