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When the internet dies, meet the meshnet that survives

If a crisis throws everyone offline, getting reconnected can be tougher than it looks, finds Hal Hodson during a test scenario in the heart of New York

By Hal Hodson

15 April 2014

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Who turned the lights out?

(Image: Iwan Baan/Getty Images)

IN THE heart of one of the most connected cities in the world, the internet has gone down. Amid the blackout, a group of New Yorkers scrambles to set up a local network and get vital information as the situation unfolds.

The scenario is part of a drill staged on 5 April in Manhattan by art and technology non-profit centre Eyebeam, and it mimics on a small scale the outage that affected New Yorkers after superstorm Sandy hit in 2012. The idea is to test whether communication networks built mostly on meagre battery power and mobile devices can be created rapidly when disaster strikes.

I’m a volunteer node in the network, and an ethernet cable runs over my shoulders into a wireless router in my left hand. It is powered by a battery in my jacket pocket.

Other routers link up with mine from a few hundred metres away. Soon I’m at the centre of a web of seven or eight nodes, connected through my smartphone. This meshnet, as it is called, is my only link to the others. The messages start coming in on my phone, flowing through an app called ChatSecure, built by the Guardian Project, a group of developers who design software for private communication. The app enables peer-to-peer communication between devices that are networked, but that don’t necessarily have an internet connection.

Building a mesh is fiddly and slow – even downloading ChatSecure involved using near field communication to establish a radio connection between nearby smartphones. I got my app from Hans-Christoph Steiner of the Guardian Project. In the absence of app stores like Google Play and the Apple store, other useful apps were made available through a hacked version of the app market software F-Droid, which let each person’s phone act as a server so others could connect and download what they need.

One of the network engineers running the drill hurries up and down West 21st Street with a laptop, monitoring the signal strength between each router, adjusting our positions to optimise the network. As the mesh gets larger and people start sending chat messages and pictures back to base through the network, the router in my hand heats up. It’s a cool feeling, though, to be exchanging data without the help of Comcast, Verizon or Google.

The Wi-Fi routers we are using and the software that binds them into a mesh are part of a networking toolkit called Commotion, developed by the Open Technology Institute (OTI) in Washington DC. This drill is not their first mesh though.

When superstorm Sandy hit the Brooklyn neighbourhood of Red Hook and the power went down, the OTI already had an experimental meshnet in place. The US Federal Emergency Management Agency managed to plug its high-bandwidth satellite uplink into it and instantly provided connectivity to the community and the Red Cross relief organisation.

“Immediately after the storm, people came to the Red Hook Initiative because they knew it was a place where they could get online and reach out to their families,” says Georgia Bullen of the OTI. The institute added more routers to the network to boost its range over the following three weeks while the power was out.

Without as much time to work out the kinks, the Manhattan meshnet isn’t as stable as Red Hook’s – the tall buildings interfere with the Wi-Fi signal, making connectivity sketchy. But the situation mirrors the challenges a meshnet might face as people struggle to get it up and running in a crisis.

The experiment also shows that digital communication is possible without big technology companies and governments – something that could be handy if a regime decided to shut down the internet to quell dissent, as happened in Egypt in 2011. “Why do we need to go through the centralised, expensive communications system?” asks Ryan Gerety of the OTI. “Maybe we should go back to the state of the internet when a lot of the work was more local.”

“The experiment shows it is possible to communicate if a regime decided to shut down the internet”

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