The location area( LA) is the place where the mobile station is currently located. This area, which forms the logical summary of several neighboring radio cells, ischecked inGSM systems by the VLR database and can comprise one or more radio zones.
The geographical size of the location area depends on the traffic density and the capacity of the visitor directory. The size should be such that subscriber data does not need to be constantly updated as the mobile station moves locally. Large location areas can be as large as 4,000 sq. km.