Public land mobile network


In telecommunication, a public land mobile network is a combination of wireless communication services offered by a specific operator in a specific country. A PLMN typically consists of several cellular technologies like GSM/2G, UMTS/3G, LTE/4G, NR/5G, offered by a single operator within a given country, often referred to as a cellular network.

PLMN code

A PLMN is identified by a globally unique PLMN code, which consists of a MCC (Mobile Country Code) and MNC (Mobile Network Code). Hence, it is a five- to six-digit number identifying a country, and a mobile network operator in that country, usually represented in the form 001-01 or 001-001.
A PLMN is part of a:

Leading zeros in PLMN codes

An MNC of two-digit form is always distinct from an MNC of three-digit form, so that, theoretically, the PLMN 001-01 is distinct from the PLMN 001-001, because of the difference in MNC length. In practice, such dualities of two-digit and three-digit MNCs with similar number value are avoided. An example for an actual three-digit MNC with leading zeros is 350-007 in Bermuda MCC; Bermuda also features 350-00, a two-digit MNC consisting of only zeros, and 350-01 with one leading zero.

PLMN code and IMSI

The IMSI, which usually identifies a SIM, USIM or eSIM for one subscriber, typically starts with the PLMN code. For example, an IMSI belonging to the PLMN 262-33 would look like 262330000000001. Mobile phones use this to detect roaming, so that a mobile phone subscribed on a network with a PLMN code that mismatches the start of the USIM's IMSI will typically display an "R" on the icon that indicates connection strength.

PLMN services

A PLMN typically offers the following services to a mobile subscriber:
The availability, quality and bandwidth of these services strongly depends on the particular technology used to implement a PLMN.