3. Acquittances and window evolution over time

3.1 Compensation for the negative effects of delayed acknowledgements

Both the slow start and congestion avoidance algorithms and sliding window flow control use the new ACKs to evolve the transmission window in sequence number space. However, there is a fundamental difference in the way the information conveyed by the ACK is used by each of these mechanisms:

• the sliding window mechanism advances the left border of the window according to the value of ACK's N˚ field, in other words, according to the number of bytes acknowledged;

• on the other hand, the increase in window size due to congestion control (in the absence of losses) is based on the quantity of ACK segments received, independently of the volume...