Question: In an IMS-based VoIP session, which functional element(s) can provide the trigger for Content of Communication (CC) interception for a PDN-GW/GGSN?
Option 1: S-CSCF or AS
Option 2: P-CSCF
Option 3: IBCF or MGCF
Option 4: IMS-AGW or TrGW
Explanation: In the context of IMS-based VoIP, for a PDN-GW/GGSN to perform CC interception, the trigger is provided by a specific functional element. According to the described architecture, the P-CSCF acts as the CC Interception Triggering Function for both PDN-GW/GGSN and IMS-AGW, making it responsible for triggering CC interception at the PDN-GW/GGSN. This highlights the role of P-CSCF in managing and coordinating lawful interception activities within the network.