Question: How does an S-CSCF/I-CSCF handle the priority of a response when receiving it without a DRMP (Diameter Routing Message Priority) AVP, assuming it supports the Diameter message priority mechanism?
Option 1: According to the priority level of the corresponding request
Option 2: Based on a default priority level predefined by the network operator
Option 3: By always assigning the highest priority to ensure timely delivery
Option 4: It ignores priority handling for responses without a DRMP AVP
Explanation: When an S-CSCF/I-CSCF receives a response without a DRMP AVP, it prioritizes the received response according to the priority level of the corresponding request, ensuring consistent handling and maintaining the intended priority for related messages.