UTRAN

The UMTS Terrestrial Radio Access Network (UTRAN) is the fixed network infrastructure that contains the facilities for the transmission to and from the mobile users over radio. The components of the UTRAN are the base stations, which are called Node B in UMTS, and control nodes, which are called Radio Network Controller (RNC). The Radio Network Controllers are connected to the Core Network (CN).

The interface for the transmission to and from the mobile users is called the UTRA.