Question: In a UTRAN Iu interface, what is the primary purpose of the SRNS DATA FORWARD COMMAND message sent from the Core Network (CN) to the Radio Network Controller (RNC)?
Option 1: To establish a new connection for voice calls in an intra-system handover.
Option 2: To trigger the transfer of N-PDUs from the RNC to the CN during intersystem change or specific scenarios related to General Packet Radio Service (GPRS).
Option 3: To manage the allocation of radio resources for User Equipment (UE) in idle mode.
Option 4: To initiate a connection-oriented signalling bearer for SMS message transmission.
Explanation: The correct answer, Option 2, accurately reflects the purpose of the SRNS DATA FORWARD COMMAND as described. This message is specifically used to trigger the transfer of N-PDUs (Network Protocol Data Units) from the RNC to the CN, particularly in scenarios involving intersystem change or specific GPRS-related cases. This highlights its role in managing data transfer between different network systems, ensuring seamless communication during handovers or system changes.