Public Land Mobile Network Identifier or with abbreviated version PLMN is a combination of MCC and MNC. It is unique value and globally used to identify the mobile network that a user subscribed.
MCC: Mobile Country Code is used in wireless telephone networks such as GSM, CDMA, WCDMA or LTE in order to identify mobile user belongs to which country. MCC consists of 3 decimal digits.
MNC: Mobile Network Code is also used in wireless telephone networks in order to identify mobile user belongs to which mobile network. MNC consists of 2 or 3 decimal digits.
PLMN is alpha character
ex: vodafone uk plmn = GBRVF