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STOMPBOX

MOBILE HOTSPOT

TURN YOUR CAR INTO A WI-FI HOTSPOT, THEN USE GPS AND WEBCAM INPUT TO MAP YOUR CURRENT LOCATION ONLINE AND AUTO-GENERATE A PHOTO TRAVELOG. BY TOR AMUNDSON

When Verizon released its new BroadbandAccess that functions like a computer hard drive but is
service, I had to give it a try. $80 a month for DSL- tougher and more vibration-resistant.
like speeds in many cities? Yes, please! The Wi-Fi interface is simple. The Linux driver
I subscribed, bought the 5220 PCMCIA card, and HostAP can run an access point from any 802.11
it worked. But the card’s antenna was so weak that card with a Prism2 chipset. You simply configure
I often had to rotate my laptop. Also, it only served your choice of SSID and WEP key and turn it on.
one computer. What if I wanted to run multiple As for the Verizon interface, wireless network-
machines or share connectivity with friends? Then ing pioneer Phil Karn wrote a how-to on getting
it hit me: I could build the card into an access point the 5220 card to work under Linux. His solution is
and install it in my car with some beefy antennas. I to make the system treat the 5220 card as a USB
called the project StompBox because this little box modem, and then send it the proper Hayes AT com-
would bring my own network “stomping grounds” mands to dialup Verizon’s network.
with me wherever I went. With this foundation in place, you can expand
your access point’s capabilities by adding a USB
OVERVIEW card, a GPS unit, a webcam, and other devices. I
In technical terms, the StompBox is a cellular hooked up a GPS and did some Google Maps hack-
router. Like all routers, its job is to push data back ing to create an auto-updated web page (hosted
and forth between multiple interfaces. Ours has two on my home network to avoid wireless traffic jams)
interfaces: Verizon’s BroadbandAccess and Wi-Fi. that tracked my car’s route and showed its current
I decided to base StompBox on embedded hard- location against a satellite photo. Unfortunately,
ware rather than on a laptop or full-blown PC. This this and many other bleeding-edge Google Maps
makes it cheaper, smaller, more reliable, and better hacks were rendered inoperative last May when
for “just plug and unplug” vehicular use. For the Google changed the unsupported beta API that
platform, I chose Pebble Linux, a Debian distribu- hackers’ code had been relying on. Then in late June,
tion from N YC Wireless. For hardware, I used the a Google Maps API beta was officially released, so
Soekris 4521, a compact embedded computer that now old map hacks can be repaired and new hacks
runs on 12VDC and has a great user community. All written in a more stable environment. Meanwhile,
the software needed — Pebble Linux plus drivers the StompBox’s web page also shows photos cap-
plus code — fits onto a 128MB Compact Flash card tured by a webcam pointing out of the car window.