Question: In a packet data service scenario, what triggers the transmission of charging information during an ongoing session to facilitate charging settlement and cost control?
Option 1: Only when the packet data session is terminated
Option 2: When a predefined charge value, duration, or data volume (or any combination thereof) is reached
Option 3: At fixed intervals (e.g., daily, weekly) regardless of usage
Option 4: Upon request from the User Equipment (UE)
Explanation: This option correctly reflects the requirement for supporting the transmission of charging information during the life of a packet data session. By triggering on charge value, duration, or data volume (or any combination), networks can ensure both timely charging settlement and effective cost control for services that may extend over very long periods.