How it works

From Information Without Borders

If you say, "Post the words FIDEL'S WORST NIGHTMARE to the Internet for me", to three friends,

And if each of those friends tells three other friends,

And if four of those people have Internet connections at their homes, perhaps in other countries if you don't live in a free one,

...then your message, "FIDEL'S WORST NIGHTMARE" will be posted to the Internet for you by proxy as soon as the first of those four people gets home and gets online.

That's a sneakernet. Our technology is a standard way for your messages to ride to and from the Internet on mobile phones, PDAs, USB thumb drives, camera flash card memory, laptop hard drives, and other portable storage. Like the Internet, you don't have to think about how the sneakernet works or how it routes messages. It just does.

As people carry the devices across borders, the standard way that the machines gossip and share information doesn't change. If you live in a country where your government doesn't allow you to access the Internet then your leader's willpower alone won't stop the flow of information. He would have to stop every single CD and thumb drive because ten thousand emails could be riding on the one that gets through. He would have to search every compact flash card in every camera on every tourist. He would have to be sure that he knows what portable storage looks like as it gets smaller and more diverse. A sneakernet raises the bar for dictator performance, forcing any leader who wants to repress Internet access to stop every single device, every single day. Direct Internet lines are easy for police to detect and stop, and radio signals can be jammed. But people will always find creative ways to smuggle things to places.

For a technical explanation of how an SNP sneakernet works, please refer to the formal specification document, IWB RFC-1: SNP Overview.

Bucket brigade

An SNP sneakernet can act like a bucket brigade to bring two-way information pipelines into extremely remote areas, perhaps a deep rainforest. For example:

Alex wants to send an email to Amnesty International, for private reasons that are none of our business. Alex lives in a small village in the middle of a rain forest, a hundred miles up a series of rivers from the nearest town with an Internet connection. Alex has had no education and can't read or write.
Alex visits Bob, the guy in his village who has that thing for sending messages to other places that the foreigners brought. Alex tells Bob a message to send to the Amnesty people, and Bob taps on the email thing for a few minutes.
The SNP software on Bob's PDA encrypts the email message into numbers, with a serial number for a destination address. Anybody who steals the email thing and looks at it can't read the message that Alex gave to Bob. They can't tell that it came from an email address associated with Alex. They can't tell that it's addressed to Amnesty International.
When Chuck comes up the river in his boat with things to sell, Bob meets with him. While they are talking at the dock, the things beep in their pockets to let them know that everybody's email is working. It just does that when they get within about 30 feet of each other and neither of them really knows much about it. Sometimes Bob's thing goes off in his pocket when he's by the river when boats go by without stopping. Bob and Chuck just know that they have to keep the things charged and on for everybody's email to work.
Chuck goes down the river to another trading post where Dave lives. The next day, Dave goes down the river to the city. He gives that email thing in his pocket to Eddie, the foreigner who brings the emails for the people up the river.
Eddie's computer has an Internet connection. The SNP software on Eddie's notebook connects to a data relay server on the Internet, which fetches new email and web pages for the people who Eddie's computer has gossiped with recently, directly or indirectly. It puts a lot of messages for a lot of people on Eddie's computer, new stuff for everybody on the list to spread back to people up the river along the grapevine.
The data relay server is the only thing that can decrypt Alex's message from numbers into an email message, because of the way that the encryption works. Even Eddie can't read any of the emails. While the data relay server is giving Eddie new information for people upstream, it also sends the email to Amnesty International. The "From" line on the email is an email address just for Alex. If anybody replies then the data relay server can get the reply email back up the river to Alex.