Question: What is the purpose of the SECURITY MODE COMPLETE message in the Evolved Packet System (EPS)?
Option 1: To initiate a security mode command from the network to the User Equipment (UE).
Option 2: To respond to a security mode command from the network and confirm the UE's security mode.
Option 3: To request a security mode command from the UE to the network.
Option 4: To indicate an error in the security mode setup between the UE and the network.
Explanation: The SECURITY MODE COMPLETE message is sent by the User Equipment (UE) to the network in response to a SECURITY MODE COMMAND message, indicating that the UE has completed the security mode setup as instructed by the network. This message confirms the UE's security mode and ensures secure communication between the UE and the network.