The mobile network contains many RNCs and BSCs. The RNCs connect to the 3G sites, and the BSCs connect to the 2G sites.

In addition, every 3G or 2G sites, is divided into several cells.

Every group of 3G or 2G cells, are grouped into a Routing Area 'RA'. and every group of Routing Areas, is grouped into a Location Area 'LA'.

PLMN

The PLMN is the identifier of the mobile newtrok.

• PLMN refers to 'Public Land Mobile Network', which is a unique identifier that identifies every mobile network.

• The PLMN consists of the MCC, and the MNC.

• MCC refers to 'Mobile Country Code', and it is a unique identifier given to each country in the world.

• MNC refers to 'Mobile Network code', and it is a unique code given to every network inside the country.

LAI

LAI is the identifier of every Location Area 'LA'.

• LAC refers to Location Area Code, and it uniquely identifies every LA, inside the network.

• While Location Area Identifier 'LAI', globally identifies every LA.

• LAI consists of the PLMN, in addition to the Location Area Code 'LAC'.

RAI

RAI is the identifier of every Routing Area 'RA'.

• RAC refers to Routing Area Code, and it uniquely identifies every RA inside the LA.

• The Routing Area Identifier 'RAI', globally identifies every RA.

• RAI consists of the LAI, in addition to the Routing Area Code 'RAC'.

CGI

• The Cell Global Identifier 'CGI', globally identifies every 2G cell.

• And it consists of the LAI, in addition to the Cell Identity 'CI'.

• While, the Cell Identity 'CI' uniquely identifies every 2G cell inside the LA.

SAI

• Service Area Identifier 'SAI',  identifies the 3G cells. a SA may contain one or more 3G cells

• SAI consists of the LAI , in addition to the Service Area Code 'SAC'.

• The SAC is unique under the same LA.