How you can anonymously use public Wi-Fi from miles afar

Benjamin Caudill, founder of Rhino Security Labs, is scheduled to demonstrate at the upcoming DefCon a new device that could help users achieve and maintain their online anonymity.

“While a range of technologies (such as ToR) can provide some level of anonymity, a fundamental flaw still exists: a direct relationship between IP address and physical location,” he explains. “If your true IP is ever uncovered, it’s game over – a significant threat when your adversary owns the infrastructure.”

Caudill’s device – dubbed ProxyHam – aims to fix that problem by allowing individuals to use a library’s or Internet cafe’s free Wi-Fi without them having to be on the premises. In fact, they can be anywhere in a 2.5 miles (a little over 4 km) radius of the device.

ProxyHam acts as a hardware proxy, routing local traffic through a distant wireless network, and is meant to be used in conjunction with other anonymising tools such as Tor.

According to Motherboard, the device is based on a Raspberry Pi computer, has a Wi-Fi card, a Wi-Fi antenna that connects it to public Wi-Fis, and a dual antenna that transmits at 900MHz in order to establish the connection to the user’s computer, which also has to have a 900MHz plugged in.

It’s clear that this device can be helpful to dissidents and whistleblowers, but also to criminals.

So far, the device looks like a big box that might be difficult to hide in a public space, but Caudill and his colleagues are working on making it fit into smaller objects (e.g. a book).

They are also looking into how to make the device self-destruct if discovered, and to make it record audio the last few seconds before that and send the it to the user, hopefully giving an indication about the identity and purpose of the discoverer.

Caudill plans to sell ProxyHam, but he will also make public full hardware schematics and code so that users can make it themselves.