Question: In NG-RAN, how does a gNodeB identify and handle duplicated warning messages received from multiple AMFs for the same warning area?
Option 1: By checking the message identifier and serial number fields, and discarding duplicates before transmitting on the radio interface.
Option 2: Through a handshake protocol with the CBCF to verify message uniqueness before transmission.
Option 3: Using a timer-based mechanism to assume messages are duplicated if received within a certain timeframe.
Option 4: By relying on the AMF to concatenate messages, ensuring no duplicates are sent.
Explanation: This is correct because, according to the specifications for NG-RAN in the context of Cell Broadcast Service (CBS), duplicated warning messages can be identified by examining specific fields within the message - namely, the "message identifier" and "serial number". Upon identifying duplicates, the gNodeB is instructed to prevent their transmission over the radio interface, ensuring efficiency and preventing unnecessary broadcasts. This approach highlights the importance of message handling in telecom networks for maintaining service quality and reducing unnecessary network load.