Question: Under what condition may an eNB (Evolved Node B) update a specific S-KWT (Security Key for Wireless Transport) associated with an AS (Access Stratum) security context?
Option 1: Periodically, as part of routine network maintenance.
Option 2: Only when the UE (User Equipment) initiates a new security procedure.
Option 3: If there is a change in the UE's QoS (Quality of Service) requirements.
Option 4: When the eNB re-keys its currently active KeNB in the same AS security context.
Explanation: This option is correct because an eNB may update any S-KWT associated with a particular AS security context specifically when it re-keys (updates the key for) its currently active KeNB within that same AS security context, ensuring synchronized security updates across related security contexts and maintaining network security integrity.