Network Performance and Operation

The GSM network can be broadly divided into- Mobile Station(MS) Base Station Sub-System(BSS) Network Switching Sub-System(NSS) Operation Support Sub-System(OSS) GSM/2G Architecture Mobile Station  :   ME(Mobile Equipment)  :Hardware used by subscriber containing IMEI(International Mobile Equipment Identity). SIM(Subscriber Identity Module)  :Detachable smart card containing IMSI(International Mobile Subscriber Identity).      2.   Base Station Subsystem  : BTS(Base Transceiver Station)  :Sends & Receives signals from MS. Also does Encoding, Multiplexing, Encryption, Modulation, ..etc. BSC(Base Station Controller)  :Controls group of BTS, Allocation of radio channels, Handover from one BTS to another.      3. Network Switching Subsystem  : MSC(Mobile Switching Centre)  :Performs call routing, call setup & call switching. Communicates with other NSS component like HLR ,VLR, AUC &EIR, Management of  mobile services like registration, authentication, ..etc. HLR(Home Location Re