Enterprising amateur radio operators in Texas, over the past several years, have created a wireless high speed data network, called HSMM-MESH or Broadband-Hamnet, completely independent of the internet. The map above is the network built by Hams in Austin, Texas. Basically it’s a bunch of hacked Linksys routers connecting wirelessly over a wide area. Plug a laptop into any of the routers and you can trade messages, files and live video back and forth.

This is possible because it just happens that the frequency range of off the shelf wireless routers overlaps with amateur radio frequencies making it legal for Hams to boost the range of these devices. That and the fact that several models of ubiquitous Linksys routers are cheap and easy to hack.

Photo: Texas Ham Radio

All you do is take your Linksys router, screw in a better antenna (note the one above made with a tin can), load some open source software on to it, scatter them around town and you’ve got a wireless data network. Note that the routers in this configuration are communicating with each other. To hook your laptop into the network you have to connect it via an Ethernet cable to one of the nodes or set up a wi-fi network at a node. The routers can even be powered by small 12 volt batteries or solar panels. To be clear, this is a wireless network that is independent of the internet (though you could route the internet over it). Such a network could be used in an emergency such as an earthquake or weather event to send digital messages. It’s also the means by which I could continue to send out cute cat photos even if things go full-on Cormac McCarthy

You could use this same hack, not exactly legally, to solve networking problems in a large house, business or rural property. And the same method has been used to set up data networks in developing countries. In practice it’s doubtful that the Man would ever get around to busting someone without a Ham license from setting up a network or routing the internet over it. As long as you’ve got line of sight between your antennas it’s possible to send information over impressive distances–with the right antenna, some Hams have managed to get the signal out as far as ten miles with a stock router and no boost in power. And the network is self healing. If one router goes out the other routers take on the traffic.

For more info on how to set up a network like this see www.broadband-hamnet.org. or watch this series of videos. There’s also a free e-Book: Wireless Networking in the Developing World.

Cat photo kidding aside, this relatively simply hack has potential to help a lot of people.

This post was inspired by a lecture given by Gary Wong, W6GSW at the Pasadena Radio Club.