4.2.4 On the Sender when receiving the acknowledgment payload from the receiver

  1. The Sender updates the circular lower bound of the active range of the Sender window buffer to 1 beyond the current sequence number and marks it as Received. Any sequence numbers circularly below this number are also marked as Received (section 3.1.1.2.1).

  2. The sequence number is forwarded to the Sender reliability controller, and the corresponding copy of the original data packet is removed and discarded from the temporary buffer (section 3.1.1.2.4.1).