3.2.3.5.4.4 STATE_SEND_FRAGS
The server MUST send a burst of RESPONSE fragments and update the Sent Fragment List. The sliding window algorithm for RESPONSE fragments is implementation-specific. For more information, see section 3.2.1.1.1.
The Call State changes to STATE_COMPLETE (see section 3.2.2.1.10) in one of the following conditions:
If a request is received with the PF2_UNRELATED flag cleared and a sequence number greater than the activity's previous call.
If the response fragments are acknowledged by the client, with respect to the packet's Header.Flags.Nofack flag, as specified in section 3.2.2.5.3.