Question: In UTRAN Iu interface, who allocates the RTP session identifier for the uplink direction when establishing an RTP session upon a radio access bearer service request?
Option 1: Both CN and UTRAN allocate the identifier jointly
Option 2: The UTRAN allocates identifiers for both downlink and uplink
Option 3: The Core Network (CN) allocates the RTP session identifier for the uplink
Option 4: The allocation is dependent on the type of radio access bearer service requested
Explanation: According to RTP Session Management principles, the Core Network (CN) is responsible for allocating the RTP session identifier specifically for the uplink direction, highlighting the divided responsibility between CN and UTRAN in managing RTP sessions.