VLR

Visitor Location Register (VLR) is a database - part of the GSM mobile phone system - which stores information about all the mobiles that are currently under the jurisdiction of the MSC (Mobile Switching Center) which it serves. Of all the information it stores about each MS (Mobile Station), the most important is the current LAI (Location Area Identity). LAI identifies under which BSC (Base Station Controller) the MS is currently present. This information is vital in the call setup process.
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