Article on " CELLULAR NETWORK COMPONENTS"

CELLULAR NETWORK COMPONENTS

BTS (Base Transceiver Station)-main component of a cell and it connects the subscribers to the cellular network; for transmission/reception of information it uses several antennas spread across the cell.

BSC (Basic Station Controller) - it is an interface between BTSs and it is linked to BTSs by cable or microwave links; it routes calls between BTSs; it is also connected to the MSC.

MSC (Mobile Switching Center) - the coordinator of a cellular network, it is connected to several BSCs, it routes calls between BSCs; links the cellular network with other networks like PSTN through fiber optics, microwave or copper cable.

Authentication Center (AuC) -level security mechanism for a GSM cellular network is a database that stores the list of authorized subscribers of a GSM network.It is linked to the MSC and checks the identity of each user trying to connect.It also provides encryption parameters to secure a call made in the network.

Home Location Register (HLR) - is a database maintained by the service provider containing permanent data about each subscriber (i.e. location, activity status, account status, call forwarding preference, caller identification preference).

Visitor Location Register (VLR) - database that stores temporary data about a subscriber; it is kept in the MSC of the of the area the subscriber is located in; when the subscriber moves to a new area the new MSC requests this VLR from the HLR of the old MSC.

Equipment Identity Register (EIR) - database located near the MSC and containing information identifying cell phones.