Question: What action can the Mobility Node (MN) take if it receives a RRC counter check response from the UE that contains one or several PDCP COUNT values?
Option 1: The MN will always release the connection.
Option 2: The MN will ignore the response and continue with normal procedures.
Option 3: The MN may release the connection or report the difference of the PDCP COUNT values to the serving AMF or O&M server for further traffic analysis.
Option 4: The MN will request another counter check procedure from the UE.
Explanation: According to the specified signalling procedure, if the MN receives a RRC counter check response from the UE that contains one or several PDCP COUNT values, it has two possible actions. It may choose to release the connection, which could be a security measure to prevent potential attacks. Alternatively, it can report the difference of the PDCP COUNT values to the serving AMF (Access and Mobility Management Function) or O&M server for further traffic analysis, such as detecting an attacker. This allows for flexibility in handling potential security threats based on network policies and configurations.