Building a Subversive Grassroots Network
http://spectrum.ieee.org/telecom/internet/building-a-subversive-grassroots-n... Building a Subversive Grassroots Network How Commotion Wireless plans to enable digital communication in the face of an Internet shutdown By Ritchie S. King / July 2011 Photo: Patrick Baz/AFP/Getty Images 26 July 2011bShutting off digital communication is a new addition to the dictatorbs tool kit. This year, between 28 January and 2 February, Hosni Mubarak shut down Egyptbs Internet and cellphone service, hobbling protestorsb ability to organize. In Libya, the Internet was suspended for 7 hours in February, and in June, the Syrian government cut off most of the countrybs access for three days. Fortunately, in a world full of hackers, technology is hard to control, even for autocrats. Hackers are creating a way for citizens to build their own communication networks from the ground up, using computers, cellphones, and wireless routers. Such networksbcalled mobile ad hoc networks, or MANETsbwould circumvent centralized communication hubs, enabling users to talk and share information in the face of a shutdown. The Open Technology Initiativebpart of the public-policy think tank New America Foundationbrecently received a US $2 million grant from the Department of State to help coordinate its MANET development effort, called Commotion Wireless. The organizationbs goal is to get MANET technology ready for use in areas that have oppressive regimes. The project should be completed by the end of next year, according to Sascha Meinrath, the initiativebs director. While Commotion has only four full-time team members, it relies on some programming (some of which it pays for) from the open-source community. "For us, this is about a call to action," Meinrath says. Commotionbs ultimate vision is to build software packages for cellphones, laptops, and wireless routers that would be able to create both Wi-Fi and cellular networks on the fly. Once a network is established, even people who havenbt installed the software could connect. And if any node in a Wi-Fi network is connected to the Internetba router with a directional antenna has a range that is tens of kilometers and could easily cross a borderbthen everyone in the network would have access. The software packages could come in a number of physical forms, according to Meinrath: CDs, thumb drives, SD cards. And when the network is up, MANET software could be transferred using Bluetooth or downloaded from the network itself. "So many vectors could be used to spread it that a regime stands no chance of stopping them all," Meinrath says. A MANET isnbt just a network of high-tech walkie-talkies; devices need to do more than communicate directly with one another. Any two connected users need to be able to share information, even if one of them is in Tahrir Square and the other is on the outskirts of Cairo and their devices are mutually out of range. That means every computer and cellphone node in a MANET has to double as a router, relaying information on behalf of other users so data can hop all the way across the network. To do that effectively, the network has to know the best path between any two devices, something that changes as people move around. There are plenty of protocols already in use that tell devices how and where to relay information. For instance, the Optimized Link State Routing (OLSR) protocol, which Commotion plans on employing, is currently being used in a grassroots MANET called FunkFeuer, based in Vienna. FunkFeuer has 1200 nodesbboth personal devices and dedicated rooftop wireless routersband was created by tech-savvy citizens as a test network for OLSR. "Webve made it massively scalable," says Aaron Kaplan, one of the founders of FunkFeuer. "Webve been using it to have a community wireless network, and itbs been running very well." OLSR works by telling each device in the network to send out a "hello" signal to all the other devices in range. That way, a given device is introduced to all of its neighbors. Then each device sends out the list of these neighborsba kind of neighborhood map (though one that doesnbt have exact geographic information). The protocol takes all the neighborhood maps from all the devices and combines them into an overall network map, refreshing about every 2 seconds. Before OLSR can be employed to bypass a throttled Internet, the technology needs to "move out of the geek-o-sphere and into the mainstream," Meinrath says. The key, he adds, is to make it really easy to install and use. The installation media that Meinrath envisionsbthumb drives and the likebwould be both clandestine and user friendly. A CD-ROM, for instance, could automatically install OLSR if it was put into a computer on booting up. And with a thumb drive or an SD card, installation would involve a mere click of the mouse. In addition to making it easy to set up a MANET, Commotion needs to make sure that the ad hoc networks are secure and anonymous so that citizens can use them without being afraid of persecution. To do this, Commotion will be adding a piece of software called Tor, which masks the sources and destinations of network traffic, and testing it in urban areas in the United States, such as Detroit, Washington, D.C., and Philadelphia. "Before we put peoplebs lives on the line, we want to test this out in a real-world setting," Meinrath says. Commotion will spend the next year or so doing research and corralling the open-source community to develop and combine a variety of software packagesbnot only OLSR and Tor but also a few others, including OpenBTS, which allows less-savvy users with cellphones to connect to a MANET without installing OLSR. "For Grandma Betty, thatbs the solution that works," as Meinrath puts it. After that, theybll spend six months field-testing what they have in the United States. "This is something that is under rapid evolution," Meinrath says. "Check back in three months and things will be completely different."
participants (1)
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Eugen Leitl