Question: What happens to the new mapped EPS security context if an inter-system change from A/Gb mode or Iu mode to S1 mode in EMM-CONNECTED mode fails?
Option 1: The MME and UE will use the new mapped EPS security context for all future handovers to E-UTRAN.
Option 2: The MME and UE will update the existing EPS security context with the new mapped one, ensuring seamless handover.
Option 3: The MME and UE will ignore the new mapped EPS security context and continue using the old one.
Option 4: The MME and UE shall delete the new mapped EPS security context.
Explanation: If an inter-system change from A/Gb mode or Iu mode to S1 mode in EMM-CONNECTED mode fails, both the MME and UE are required to delete the newly created mapped EPS security context. This is necessary to maintain network security by preventing partially established security contexts from being used. Deleting the new mapped EPS security context ensures that any sensitive information associated with it is removed, and the network remains secure.