Can We All Stop Connecting to "Free Public WiFi" Now?
Anyone who regularly uses their laptop or iPhone to search for a public Wi-Fi hotspot, has probably encountered the SSID called "Free Public WiFi" more than once. Those who've tried connecting to it almost certainly failed in their quest to reach the Internet. Hopefully, nothing worse happened.
This phenomenon has been afflicting people in areas with public Wi-Fi for years, wasting their time and unnecessarily exposing their computers to network attacks. Fortunately, taking a few simple actions now will reliably avoid this particular problem in the future.
As for technical details: The "Free Public WiFi" SSID is almost never a gateway to an actual hotspot. It's typically an ad hoc Wi-Fi advertisement from someone else's nearby Windows laptop instead. Why? In certain situations, Microsoft Windows will save the SSID of an ad hoc network connection you've made in the past, and later, configure your computer to advertise itself as a new ad hoc network with the same name. This effectively proliferates frequently-used ad hoc network names from one Wi-Fi device to the next, like a chain letter.
Because "Free Public WiFi" is one SSID that folks apparently cannot resist initiating connections to, that name has spread to the Wi-Fi configuration databases of devices worldwide. Avoid connecting to a network with this name unless you are certain it belongs to a valid nearby hotspot. Additionally, to prevent your devices from picking up and proliferating SSIDs, you must disable the automatic connection feature for ad hoc networks whenever within reach of other people's Wi-Fi equipment.
The Ongoing "Free Public WiFi" Phenomenon Explained - Dwight Silverman @ chron.com in 2006, by Zaib Kaleem @ wlanbook.com (2007) and by Michael Horowitz @ cnet.com in 2008Public Wi-Fi at an Airport - Photo: Jamie Rector / Getty Images
Thank you for providing an informative site that covers such a complex subject. Keep up the good work.
Yeah, thanks, great advice. Would this be an issue with a Mac and/or iPhone? I ran into a persistent Free WiFi connection underground on the F Train to Brooklyn with my iPhone. Lasted the entire ride, so must have come from somebody nearby.
Yes, thank-you for this. I have been picking up the “free public wifi” signal for year and never remembered to research it until now. The reason is I now work on my laptop on the 2 train and, like the reader above, I grab that signal from time to time.