Question: In MBMS file repair, after determining the FDT Instance URI for a session occurrence, what action does the UE take before requesting the FDT Instance via HTTP GET method?
Option 1: Immediately requests the FDT Instance to expedite file repair
Option 2: Waits for the Back-off Time to elapse as specified in the session schedule
Option 3: Sends a request to the MBMS server to confirm session completion
Option 4: Initiates a new session occurrence to retrieve missing files
Explanation: To prevent overwhelming the server with simultaneous requests and ensure orderly retrieval of file repair information, the UE is mandated to wait for a specified Back-off Time after the transmission of files for a session occurrence is considered complete. This waiting period allows for efficient network resource utilization and reduces congestion, highlighting the importance of timing in telecom networks for successful media transfer and session management.