What is 2G or GSM ?

2G was the next generation version of 1G . It was much better and much or reliable. 2G also known as GSM (Global System for Mobile communication) .

It has provided 9.6Kbps of data rate. FDMA and TDMA technology was used for communication. 

2G is a Second generation of network and it was Commercially launched in 1991 in Finland.

In 2G Conversation were digitally encrypted so security was much better than 1G.  It is More efficient on spectrum and use Digital voice and signaling. First time data services (SMS) were introduced. It uses Band Width of 200KHz.

GSM Network :

The GSM network is divided into :

Base station subsystem (BSS)

Network Switching Subsystem(NSS)

Network Management Subsystem(NMS)

Functions of NSS 

 NSS is a core network there are many sub component of NSS such as MSC , VLR , AC , HLR , GMSC , EIR .

Call controlling  :- NSS is responsible for identifies the subscriber , established a connection and ensure after call disconnect clear the connection . This is the most important functionality .

Charging :- NSS collects charging information regarding the call and store the information in Charging data Record (CDR) and later its transferred to the billing centers.

Subscriber data handling :- Subscriber data handling happens in Home Location Register (HLR ) for permanent subscribers and for temporary subscribers relevant data is stored in Visitor Location Register (VLR) . When a person buys subscription its data is stored in HLR and if person moves from one place to another place its data is store in VLR .

Signaling :- This applies to interfaces with BSS and PSTN . Communication between different Network Elements happen over specific over protocols defined in signaling.  

Mobility management  :- One of the most important task of mobile network is to ensure provide proper service and keep track of subscriber when if subscriber is moving from one place to another place . when ever user or subscriber moves one place to another place with the mobility management data is updated and proper service is provided to that person .

Function of BSS 

Work of managing RADIO network is done by BSS . BSS is a wireless part of mobile Network for more understanding it can be compared with Wi-Fi . MSC connect to multiple BSS . BSS cover a long distance area .

Radio Path Control

BTS and TC Control

Synchronization with UE(user equipment) 

Mobility management 

transcoding 

Statical data collection 

Function of NMS

Network Management Subsystem monitor various functions and elements of network.

Fault Management :- As part of Fault Management alarm reports are generated . As part of fault management all information about Events and Alarms are given to operator  .

Performance Management :- As part of performance management measurement of data of network elements happens and the performance of the elements is majored .

Configuration Management :-  As part of configuration management all the configuration of the network elements are managed .