Mobile architecture (GSM 03.02)
Public Land Mobile Network (PLMN) as GSM architecture:
A Public Land Mobile Network is established and operated
by an administration or RPOA (Recognized private operating
agency) for the specific purpose of providing land mobile
telecommunication services to the public.
A PLMN may be regarded as an extension of a fixed network
(e.g. PSTN - Public Switched Telephone Network) or as an integral
Functionally, the PLMNs may be regarded as independent
telecommunication entities.
Different PLMNs may be interconnected through the PSTN.