If James Bond needed to use bitcoin on a secret mission in the jungle, he probably couldn't drop by a Starbucks to use the wifi.
Since internet connections aren't always available, reliable or private, cryptocurrency users need alternative ways to connect to the network. So the New York-based startup goTenna, founded in 2012 by Brazilian siblings Daniela and Jorge Perdomo, is partnering with Samourai Wallet to launch an Android app this summer that allows users to send bitcoin payments without an internet connection.
Announced Monday, the txTenna app will enable users to sync up their mobile with a goTenna device, which costs $179 per pair, then toggle the wallet app's settings to transact offline and send the bitcoin.
"You need to be able to spend your bitcoin even in disaster areas," goTenna engineer Richard Myers told CoinDesk, citing the Perdomo siblings' recent work in Puerto Rico, where goTenna devices helped people reconnect after Hurricane Maria. "As long as you have a way to charge your phone, you can be up and meshed and communicating."
The signal needs to be within roughly a mile of another goTenna device to relay the message across the mesh network, a decades-old system for using the internet without wifi or a landline. So far, goTenna has sold more than 100,000 devices that let users tap into the mesh network.
If the offline bitcoin user is within a mile of another active device, the transaction could bounce across the mesh until it reaches a user with an internet connection.
"It offers an alternative that is more censorship-resistant," Myers said, adding:
"It's going to obscure who you are and where you're at when making these transactions. So that's a big privacy advantage there."
This system uses a free, unlicensed radio frequency, and it isn't the first partnership to explore such potential for cryptocurrency networks.
It takes a village
Stepping back, a variety of projects since the Cold War have used relatively cheap and mobile radio setups to broadcast across firewalls and oceans.
Last year, renowned cryptographer Nick Szabo and blockchain engineer Elaine Ou published a proposal detailing how weak-signal radio transmissions could help boost security and the diversity of connections across the bitcoin network.
Then, in December, after the U.S. Federal Communications Commission repealed "net neutrality," fans of ethereum, the world's second most popular blockchain network, started flocking to mesh network technology meetups.
When net neutrality rules expire next month, internet service providers will no longer be barred from favoring or blocking specific websites and communities. It's an opportune moment for censorship-resistant tools for bitcoin transactions.
Perhaps the most important aspect of txTenna is that the cryptocurrency wallet will be an open source project.
Indeed, it was Samourai Wallet's open source communication tools on Github that first inspired goTenna's team to reach out to the bitcoin startup. The same txTenna code could theoretically be applied to iOS wallet applications as well.
As Myers explained:
"It absolutely could work with any software wallet and they [Samourai Wallet developers] are not writing it specifically for the Samourai wallet anyway. It will be something any wallet provider could send transactions through."
Image of Daniela and Jorge Perdomo with goTenna devices via goTenna