target = "https://www.rfc-editor.org/rfc/rfc9002#section-7.2" # 7.2. Initial and Minimum Congestion Window # # QUIC begins every connection in slow start with the congestion window # set to an initial value. Endpoints SHOULD use an initial congestion # window of ten times the maximum datagram size (max_datagram_size), # while limiting the window to the larger of 14,720 bytes or twice the # maximum datagram size. This follows the analysis and recommendations # in [RFC6928], increasing the byte limit to account for the smaller # 8-byte overhead of UDP compared to the 20-byte overhead for TCP. # # If the maximum datagram size changes during the connection, the # initial congestion window SHOULD be recalculated with the new size. # If the maximum datagram size is decreased in order to complete the # handshake, the congestion window SHOULD be set to the new initial # congestion window. # # Prior to validating the client's address, the server can be further # limited by the anti-amplification limit as specified in Section 8.1 # of [QUIC-TRANSPORT]. Though the anti-amplification limit can prevent # the congestion window from being fully utilized and therefore slow # down the increase in congestion window, it does not directly affect # the congestion window. # # The minimum congestion window is the smallest value the congestion # window can attain in response to loss, an increase in the peer- # reported ECN-CE count, or persistent congestion. The RECOMMENDED # value is 2 * max_datagram_size. [[spec]] level = "SHOULD" quote = ''' Endpoints SHOULD use an initial congestion window of ten times the maximum datagram size (max_datagram_size), while limiting the window to the larger of 14,720 bytes or twice the maximum datagram size. ''' [[spec]] level = "SHOULD" quote = ''' If the maximum datagram size changes during the connection, the initial congestion window SHOULD be recalculated with the new size. ''' [[spec]] level = "SHOULD" quote = ''' If the maximum datagram size is decreased in order to complete the handshake, the congestion window SHOULD be set to the new initial congestion window. ''' [[spec]] level = "SHOULD" quote = ''' The RECOMMENDED value is 2 * max_datagram_size. '''