Walking around town with a laptop
uncovers interesting tidbits about the neighbors. Kristen McQuillin scans the airwaves.
driving" is the latest craze in the US. This is not about tanks, or Hummers, or even
road rage, but wireless laptops. Armed with an 802.11 wireless card, a packet sniffer, and
a GPS system, American computer hackers are hopping into their cars to make maps of
wireless computer networks around town. Why? Because once an open wireless network is
discovered, a few minutes of observation and a little tinkering lets the observer join the
network to use it for Internet access, spying on neighbors, or a bit of industrial
Wireless networks are run on radio frequencies and normally broadcast within about a
100-meter radius. Instead of music, they broadcast network packets-the inscrutable
information that computers use to talk to one another-that allow network users with
laptops to roam freely within broadcasting distance. It's the network packets that war
drivers are peeking into.
Because wireless networks broadcast to anyone who is listening, authorized users or not,
it's wise to install security on them. WEP, Wireless Encryption Protocol, is built into
wireless cards and relatively simple to implement. It takes each packet and encrypts it so
that only a listener with the right key can decode it and use the information. A truly
determined hacker can crack WEP encryption in less than a week, but if repelling casual
onlookers is all that's necessary, WEP is adequate. However, many networks don't use it.
In the spirit of experimentation-but lacking a car-we decided to stroll through our
neighborhood with a wireless laptop. No one suspected we were "war walking," but
passersbys turned their heads to watch us using the computer and exclaiming in glee as we
investigated our local airwaves.
In the course of three blocks, six networks appeared. Only one was encrypted, leaving five
open to our sniffer. The sniffer looks for traffic on the network and displays the IP
addresses of the local computers and the ones they are connecting to (websites and email
servers, for example). We took at peek at the traffic on three of the networks and found
one user logging onto AOL and another at Yahoo! Japan. The third sniff got us connected to
a corporate intranet where we viewed some web pages under development.
If we had been really lucky, we might have found a printer on the network and surprised
someone with a friendly message. Our dark side wished we'd found someone surfing porn
(great blackmail fodder), but our victims were innocent, and our war walk was harmless to
everyone. But consider this: if we can read your network traffic so easily, so can
competitors, blackmailers, and malevolent hackers.
Won't you be my neighbor?
Not everything about open wireless is sinister. As the technology becomes truly affordable
(a wireless card costs about JY13,000), grassroots organizations in the US, Europe and
Australia are setting up wireless community networks that share high-speed Internet
access. Each participant registers his computer and connects to others in the wireless
neighborhood. One or more of the members of the network have broadband access to the
Internet, creating a shared system.
To date, nobody's created a Tokyo neighborhood wireless community, but considering the
concentration of networks in our neighborhood alone, it shouldn't be too long before we
see them springing up.
In the meantime, SpeedNet, a consortium of TEPCO, Microsoft and SoftBank, is implementing
a wireless Internet system for a fee. With wireless transmitters atop utility poles in
locations just outside Tokyo, SpeedNet is poised to bring high-speed Internet to such
exotic locales as Tsukuba, Chiba, and Kanagawa.
Would you like wireless with that?
Restaurants and coffee shops are already getting into the wireless act. Select Starbucks
locations in the US offer wireless access and the chain hopes to expand that service to
more outlets. Yahoo! Café in Harajuku is situated on the second story of a large
Starbucks and offers free Internet access from their showcase of wireless laptops. You
don't get the mobility of wireless, though, since Yahoo's laptops are rooted to desks.
MOS Burger is dishing up wireless in five of its stores in an experiment that runs through
December. They've teamed up with NTT Communications and Malco to offer free Internet
access to customers in Ginza, Shibuya, Kanda, and elsewhere.
If you're hungry for a more substantial meal with your email, Brendan's Pizzakaya in Nishi
Azabu is offering Internet access to diners who bring their own wireless-enabled laptops.
If you don't have your own wireless gear, don't despair. Download Station in Otemachi will
loan you a laptop and wireless card for up to three hours that you can use for free at any
of the businesses in their complex, including Town Cryer, a British pub. What can compare
to surfing the web while drinking a Guinness?
Yahoo! Café (Starbucks), 5-11-2
Jingumae, tel: 03-3797-6821
Brendan's Pizzakaya, 3-1-19-203
Nishi-Azabu, tel: 03-3479-8383
Town Cryer, Tokyo Sankei Bldg 6F, 1-7-2
Otemachi, tel: 5204-2201