3.1.5.3 Receiving a Packet Pair Summary message
When a Packet Pair Summary message arrives through a TCP Socket, it is correlated back to a Packet Pair Session object.
If the per-session Expected Message field is not equal to 0x0A (Packet Pair Summary), the initiator MUST fail the Packet Pair Experiment request that instantiated the session and the associated session object is deleted.
Otherwise, the Expected Message field is set to 0x00 to indicate that the initiator is not expecting an incoming message. The initiator validates the fields in the Handshake header inside the message as per section 2.2.1.1 and section 2.2.2.7. If the header contains an invalid value, the initiator MUST fail the Packet Pair Experiment request that instantiated the session and the associated session object is deleted.
The initiator then invokes the routine identified by the per-session Estimation Callback field with the Packet Pair Summary header. If the routine returns with a success error code, the initiator MUST succeed the Packet Pair Experiment request that instantiated the session and the associated session object is deleted.