Google to Allow Users to Opt Out of WiFi Location Mapping System

Type threatpost
Reporter Dennis Fisher
Modified 2013-04-17T16:33:20


Google WiFiGoogle, which has faced a pile of criticism over its privacy policies and practices, especially as they relate to wireless and mobile devices, says it is changing the way that it maps people’s wireless access points in its efforts to provide accurate location information. The company said it is now encouraging users to add a “_nomap” extension to the SSID of their access points if they don’t want Google to map them.

The change is a small one and it doesn’t change Google’s policy overall. It puts the onus on users to make the change in their router’s configuration to prevent Google from mapping it. Whether users will make that effort–or even understand how to do it–is unclear. In most cases, users simply need to log in to the admin panel of their wireless router or access point and change the name to add the “_nomap” extension to the end.

Google and other companies use the data that access point broadcast to build a database of the access points’ location. It then uses that data to pinpoint users’ location when they’re using location-based services such as Google Maps on a smartphone or other mobile device. The data is used to supplement or replace GPS or cell-tower location data.

The practice has drawn sharp criticism from users and privacy advocates who question why the company is collecting and storing data about users’ home networks at all.

“The wireless access point information we use in our location database, the Google Location Server, doesn’t identify people. But as first mentioned in September, we can do more to address privacy concerns,” Peter Fleischer, Google’s global privacy counsel, said in a blog post explaining the change.
“We’re introducing a method that lets you opt out of having your wireless access point included in the Google Location Server. To opt out, visit your access point’s settings and change the wireless network name (or SSID) so that it ends with ‘nomap.’ For example, if your SSID is ‘Network,’ you‘d need to change it to ‘Network_nomap.'”_

There are other companies that collect and use similar data, including Apple, which became embroiled in a controversy in April when researches discovered that iPhones had a database of location data stored on them. Apple said, as Google did, that it doesn’t track users’ locations, but rather uses the data on which wireless hotspots the users have accessed to help calculate locations.

“Calculating a phone’s location using just GPS satellite data can take up to several minutes. iPhone can reduce this time to just a few seconds by using Wi-Fi hotspot and cell tower data to quickly find GPS satellites, and even triangulate its location using just Wi-Fi hotspot and cell tower data when GPS is not available (such as indoors or in basements). These calculations are performed live on the iPhone using a crowd-sourced database of Wi-Fi hotspot and cell tower data that is generated by tens of millions of iPhones sending the geo-tagged locations of nearby Wi-Fi hotspots and cell towers in an anonymous and encrypted form to Apple,” the company said in an FAQ it published after the research was disclosed.

In his blog post, Google’s Fleischer said that other companies could use the opt-out mechanism it has recommended for users, as well.