Geo-fencing (geofencing) is a feature in a software program that uses the global positioning system (GPS) or radio frequency identification (RFID) to define geographical boundaries. A geofence is a virtual barrier. Programs that incorporate geo-fencing allow an administrator to set up triggers so when a device enters (or exits) the boundaries defined by the administrator, a text message or email alert is sent. Many geo-fencing applications incorporate Google Earth, allowing administrators to define boundaries on top of a satellite view of a specific geographical area. Other applications define boundaries by longitude and latitude or through user-created and Web-based maps. The technology has many practical uses. For example, a network administrator can set up alerts so when a hospital-owned iPad leaves the hospital grounds, the administrator can disable the device. A marketer can geo-fence a retail store in a mall and send a coupon to a customer who has downloaded a particular mobile app when the customer (and hissmartphone) crosses the boundary. Geo-fencing has many uses including: Use: Fleet management, Example: When a truck driver breaks from his route, the dispatcher receives an alert. Use: Human resource management, Example: An employee smart card will send an alert to security if an employee attempts to enter an unauthorized area. Use: Compliance management, Example: Network logs record geo-fence crossings to document the proper use of devices and their compliance with established rules. Use: Marketing, Example: A restaurant can trigger a text message with the day's specials to an opt-in customer when the customer enters a defined geographical area. Use: Asset management, Example: An RFID tag on a pallet can send an alert if the pallet is removed from the warehouse without authorization. Use: Law enforcement, Example: An ankle bracelet can alert authorities if an individual under house arrest leaves the premises. See also: location-based services, geolocation, geotargeting, telemetry, machine-to-machine (M2M)