Question: In an IMS scenario, a UE moves from one access system to another but retains the same IMS contact address and serving P-CSCF. What action is typically required for its ongoing multimedia session?
Option 1: Activate IMS Service Continuity mechanisms to transfer the multimedia session.
Option 2: Update the session based on normal IMS procedures, potentially removing unsupported media types.
Option 3: Change the serving P-CSCF to accommodate the new access system.
Option 4: Terminate and re-establish the multimedia session on the new access system.
Explanation: Since the UE's IMS contact address and serving P-CSCF remain unchanged, there is no need to activate Service Continuity mechanisms. The UE may, however, update the session (e.g., remove media types not supported by the target access system) following standard IMS procedures, ensuring compatibility with the new access system without disrupting the ongoing session.