What an IMSI and PLMN is ?

IMSI

The IMSI (International Mobile Subscriber Identity) is a unique 15-digit code used to identify an individual user on a GSM network.

The IMSI consists of three components:

• Mobile Country Code (MCC)
• Mobile Network Code (MNC)
• Mobile Subscriber Identity Number (MSIN)

The IMSI is stored in the Subscriber Identity Module (SIM).

PLMN

Short for Public Land Mobile Network, a generic term for a mobile wireless network that is centrally operated and administrated by an organization and uses land-based radio frequency transmitters or base stations as network hubs. PLMNs can stand alone and interconnect with one another or connect to a fixed system such as the PSTN.

Cellular phones and mobile Internet access are two common uses of a PLMN.