14/10/2010 By http://voices.washingtonpost.com ( Source: http://voices.washingtonpost.com )

'Free Public WiFi' is a zombie network

Always frustrating and always elusive, for would-be WiFi users, "Free Public WiFi" has long been a confounding chimera. It pops up as an option in public places, especially in airports, but though it seems like a valid network, it never works. That's because it does not actually exist as a WiFi network.

Rather, it's a zombie network that connects your computer to a nearby computer, not to an Internet connection. No, it won't make your computer rise from the dead and eat your brains (though that would make for an interesting movie), but it is a network that doesn't exist and spreads from computer to computer. It is similar to a virus and could leave your computer open to a hacker's attack. It started from an old Microsoft XP glitch. NPR's "All Things Considered" explains it:

"When a computer running an older version of XP can't find any of its 'favorite' wireless networks, it will automatically create an ad hoc network with the same name as the last one it connected to -- in this case, 'Free Public WiFi.' Other computers within range of that new ad hoc network can see it, luring other users to connect."

Microsoft offers an update for the older versions of XP that can seal off this glitch. NPR says its not the only "zombie network" out there. Others exist with names like "linksys," "hpsetup," "tmobile" or "default."