location update (GSM) (LUP)

The term Location Update (LUP) is used in GSM networks for updating the information about the location, the Location Area( LA), in which the mobile station is currently located.

With a location update, the mobile station informs the GSM network in which cell within which location area it is currently located. The mobile station can move freely within a location area. A location update is only performed when the mobile station leaves the location area or after a time specified by the network operator.