Architecture of the GSM network

GSM -> Architecture

Architecture of the GSM network MobileStation BaseStationSubsystem Network Subsystem

Following is the simple architecture diagram of GSM Network. [pic]
A GSM network is composed of several functional entities, whose functions and interfaces are defined.
Figure 1 shows the layout of a generic GSM network. The GSM network can be divided into three broad parts. The Mobile Station is carried by the subscriber, the Base Station Subsystem controls the radio link with the Mobile Station. The Network Subsystem, the main part of which is the Mobile services Switching Center, performs the switching of calls between the mobile and other fixed or mobile network users, as well as management of mobile services, such as authentication. Not shown is the Operations and Maintenance center, which oversees the proper operation and setup of the network. The Mobile Station and the Base Station Subsystem communicate across the Um interface, also known as the air interface or radio link. The Base Station Subsystem communicates with the Mobile service Switching Center across the A interface.

,---------------------------------------------------------------------------,
| Um A |
| Interface A-bis Interface |
| | Interface | ,--------------------, |
| | ,-----, ,-----, | |
| | ,----------|----------, | | | VLR | | HLR | | ,-------, |
| ,-----, | ,-----, | | `-----' `-----' | | Other | |
| | SIM | | | | BTS | | ,-----, | | | ,-----, | | MSCs | |
| `--,--' | `-----'---| | | | | |--------------'-------' |
| | , | : | | BSC |-----------| MSC | | |
| ,-----, /| | ,-----,---| | | | |