What are the major functions of the RNC in UTRAN architecture?

UMTS radio access network, UTRA or UTRAN was the name for the radio access network elements of the 3G UMTS mobile phone system .

GSM EDGE Radio Access Network (GERAN) is a radio access network architecture, based on GSM/EDGE radio access technologies . The GERAN is fully harmonised with the UMTS Terrestrial Radio Access Network (UTRAN) through a common connectivity to the UMTS core network.

The Radio Network Controller (RNC) is a governing element in the UMTS radio access network (UTRAN) and is responsible for controlling the Node Bs that are connected to it .

Universal Mobile Telecommunications System (UMTS)