Question: In a scenario where the 'EPSFallbackReport' feature is supported, how does the Policy Control Function (PCF) notify the Application Function (AF) of an EPS Fallback event triggered by the Session Management Function (SMF)?
Option 1: The PCF sends an initial provisioning request to the AF with the EPS_FALLBACK cause.
Option 2: The SMF directly informs the AF about the EPS Fallback, bypassing the PCF.
Option 3: The PCF includes the EPS_FALLBACK indication in a new session establishment request to the AF.
Option 4: The PCF sends a Re-authorization Request (RAR) command with the EPS_FALLBACK cause encoded in the Specific-Action AVP.
Explanation: According to the described procedure for handling EPS Fallback reporting, when the PCF receives an indication of EPS Fallback from the SMF, it uses a Re-authorization Request (RAR) command to notify the AF. This RAR command specifically includes the EPS_FALLBACK cause within the Specific-Action AVP, ensuring the AF is informed of the fallback event in a standardized and structured manner.