Question: In an IMS Emergency Session, what determines whether unauthenticated sessions are allowed for a UE attached for EPS emergency bearer services?
Option 1: The type of Attach Request (e.g., "Emergency" vs. normal)
Option 2: The serving network policy
Option 3: The availability of a valid GUTI on the UE
Option 4: The presence of IMSI or IMEI in the Attach request
Explanation: According to telecom security architecture, the decision to allow unauthenticated IMS Emergency Sessions for UEs attached for emergency services is not based on technical parameters like Attach Request types, GUTI validity, or device identifiers (IMSI/IMEI). Instead, it hinges on the policy set by the serving network, highlighting the importance of network operator discretion in balancing security with emergency access.