Question: What action does a GTP entity take when it receives a Response message within an IP/UDP packet of a length that is inconsistent with the value specified in the Length field of the GTP header?
Option 1: Send a Response message with Cause IE value set to "Invalid Length" and log the error.
Option 2: Silently discard the message and log the error.
Option 3: Return an appropriate Request message with Cause IE value set to "Invalid overall length of the triggered response message".
Option 4: Send a Notification message to the peer GTP entity.
Explanation: According to the specifications, if a GTP entity receives a Response message within an IP/UDP packet of a length that is inconsistent with the value specified in the Length field of the GTP header, then the receiving GTP entity should log the error and shall silently discard the message.