Geeks with laptops may have more in common with the hobos of the 20th century than you might imagine. That similarity is testament to the organic and unconventional way that local area wireless networks, also known as Wi-Fi, are evolving.
Wi-Fi, the standard for broadband wireless networks, has grown rapidly over the past year as companies and individuals implement "hot spots" that offer wireless Internet connectivity within a short range, usually about 100 feet.
The networks are often available in public places, including Starbucks shops and airports. The trouble is, it's hard to know where many such hot spots are available, if they're free and if they're unsecured so anyone can use them.
Matt Jones, a London resident who swears he's not a geek, recently planted the seed for solving that problem and the idea has quickly spread around the Internet. His plan is based on a piece of hobo culture where wanderers would mark symbols on homes or buildings indicating where other hobos might work for food or find a warm place to sleep.
Jones proposed on a Web log that Wi-Fi users agree on a set of symbols that they can chalk on sidewalks or buildings to help other users find out where they can get on to the Internet. Right now, Wi-Fi users otherwise have to engage in sniffing, powering up their laptops to find out if they are in the range of wireless coverage.
"It breaks the cycle," said Jones, a designer for the BBC. "You don't have to get out your laptop to know it's there."
Jones likes the idea of using chalk instead of spray paint or stickers for a couple of reasons. "I don't want to get arrested."
Also, the coverage of wireless networks changes, as some access-point owners add security that won't allow just anyone to use it or hot spots move. "People will have to keep going around and revalidating the network," he said.
Jones calls it "warchalking," a play on the hacker term "wardialing," which refers to a hacker practice of setting computers to continually dial phone numbers until they reach one that lets them break into a network via the modem.
While the plan has generated excitement among Wi-Fi supporters on the Web, it does have some shortcomings. Currently, some companies with Wi-Fi haven't secured their networks so they inadvertently let outsiders use their networks. Warchalking would only increase the number of people logging onto those networks, which increases the chances that the Wi-Fi network owner will notice the unauthorized users.
"They'll secure it and then you've just lost your free lunch," said Navin Sabharwal, an analyst with Oyster Bay, N.Y.-based Allied Business Intelligence, a consulting and research company.
One London community Wi-Fi group worries that warchalking will make the concept of community networking — independently built Wi-Fi networks that are freely accessible by anyone — seem like a "cracker plot" and threaten its validity.
Nonetheless, a storefront in San Francisco already has put a symbol up in its window to let passers-by know they can use its network.
One enthusiast, Hunter Cheun, a computer analyst for the county of Ventura, Calif., is visiting Seattle for the July Fourth weekend and plans to spend time traveling around town, chalk and laptop in hand, marking public-access spots.
The chief information officer for the state of Utah intends to warchalk to help city workers like the police find wireless networks.
While it remains to be seen if warchalking will become widely used, the idea demonstrates the grass-roots way that Wi-Fi has grown.
Logging on to and looking for networks is technically challenging, so a subculture of Wi-Fi enthusiasts exists who try to find different ways to exploit the technology to point out its shortcomings while trying to evangelize and encourage use.
For example, a leader of Seattle Wireless, a group building a community Wi-Fi network here, recently demonstrated the security weaknesses of Wi-Fi by tracking unsecured data running over a network at a conference, then posting attendee names and passwords on an overhead projector.
Even some companies are contributing to the free-for-all.
Tully's Coffee Chairman Tom O'Keefe boasted that he doesn't have to worry about implementing a Wi-Fi strategy in his stores soon because Tully's customers can access the Wi-Fi networks spilling over from nearby Starbucks shops.