Type of site
Google Traffic can be viewed at the Google Maps website, or by using the Google Maps application on a handheld device.
Google Traffic works by analyzing the GPS-determined locations transmitted to them by a large number of cellphone users. By calculating the speed of users along a stretch of road, Google is able to generate a live traffic map. Google processes the incoming raw data about cellphone device locations, and then excludes anomalies such as a postal vehicle which makes frequent stops. When a threshold of users in a particular area is noted, the overlay along roads and highways on the Google map changes color.
Early versions of Google Maps provided information to users about how long it would take to travel a particular road in heavy traffic conditions. Traffic information was based on historical traffic data, and was not particularly accurate.
In 2004 Google acquired ZipDash, a company specializing on realtime traffic analysis. In 2007, Google integrated ZipDash's technology into Google Maps, offering traffic data, based on information gathered anonymously from cellular phone users.
Crowdsourced traffic data
Cellular telephone companies constantly monitor the locations of user devices. One tracking method is trilateration, whereby the distance (time delay) to three or more surrounding cell phone towers is measured. Another tracking method monitors the exact user coordinates determined by a GPS inside the phone. GPS-equipped cellphones began appearing in 2004, and by 2011, the U.S. Federal Communications Commission required that all new cellular phones be equipped with a GPS.
Soliciting electronic information from a large group of people this way is referred to as crowdsourcing.
Google stated: "When we combine your speed with the speed of other phones on the road, across thousands of phones moving around a city at any given time, we can get a pretty good picture of live traffic conditions".
Google Traffic is available by selecting "Traffic" from a drop-down menu on Google Maps. A colored overlay appears on top of major roads and highways, with green representing a normal speed of traffic, yellow representing slower traffic conditions, and red indicating the slowest speeds. Gray indicates there is no data available.
Users can use the "search" feature to display traffic in a particular area. For example, a user may type into the search box: "traffic near Edmonton, Alberta", to see traffic for that city on the map. Another feature uses historical data to show users the "typical traffic" for an area based on the time of day and day of the week. Google Traffic also displays "traffic incidents", such as construction, accidents, and road closures. As well, Google Traffic can be viewed while using Google Map's "directions" feature.
Google has stated: "we understand that many people would be concerned about telling the world how fast their car was moving if they also had to tell the world where they were going". Google built in a number of features to safeguard the identities and locations of users who choose to provide Google with traffic data.
Mobile devices which use Google's Android operating system come equipped with the ability to send location data to Google, while non-Android devices which use Google's map application are also able transmit their location data to Google. However, options available in each phone's "settings" allow users not to share information about their location with Google Maps. On Google's website, detailed "opt-out" instructions are available for various devices and operating systems, including Android, BlackBerry, iPhone/iPod, Palm webOS, Symbian S60, Windows Mobile, and Sony Ericsson. Google stated, "once you disable or opt out of My Location, Maps will not continue to send radio information back to Google servers to determine your handset's approximate location".
Anonymity of location data
Google has stated that the speed and location information it collects to calculate traffic conditions is anonymous. Google also identifies the start and end points of every trip it monitors, and permanently deletes that data so that information about where each user came from and went to remains private.
- "Traffic Data Availability and Colors". Google. Retrieved February 2014.
- Subramanian, Karthik; Srikanth, R. (January 21, 2014). "Now, Apps for Live Traffic Feed". The Hindu.
- Matthews, Susan E. (July 3, 2013). "How Google Tracks Traffic". The Connectivist.
- Michael Bazeley (March 30, 2005). "Google acquires traffic info start-up Zipdash". SiliconBeat. Retrieved January 8, 2008.
- Wang, David (February 28, 2007). "Stuck in traffic?". Google.
- "Real time traffic information with Google Maps". CrackBerry. March 22, 2007. Retrieved June 23, 2014.
- "Assisted-GPS Test Calls for 3G WCDMA Networks". 3G.co.uk. November 10, 2004.
- Barth, Dave (August 25, 2009). "The Bright Side of Sitting in Traffic: Crowdsourcing Road Congestion Data". Google.
- "Traffic". Google. Retrieved February 2014.
- "Opt Out of My Location". Google. Retrieved February 2014.