Question: In the context of Advice of Charge (AoC) supplementary service for MMTel sessions, what is the primary distinction between Advice of Charge for Information purposes (AoCI) and Advice of Charge for Charging purposes (AoCC)?
Option 1: AoCI provides charging information at communication setup, while AoCC provides it during the active communication phase.
Option 2: AoCI is used for voice calls, whereas AoCC is used for video calls.
Option 3: AoCI estimates costs, which may differ from the actual bill, whereas AoCC indicates the exact charge that will be made for the service used.
Option 4: AoCI requires UE capability to display cumulative charges, while AoCC only requires rate of communication service display.
Explanation: The correct answer highlights the key difference between AoCI and AoCC. AoCI provides an estimate of costs that may not reflect the final billing (e.g., due to rounding or promotional rates), whereas AoCC is designed to inform the user of the precise charge that will be incurred for using the MMTel service, ensuring transparency in billing.