If this parameter is set to 1, the maximum rate of sending a RST segment is controlled by the ndd parameter, tcp_rst_sent_rate. If this parameter is set to 0, no rate control when sending a RST segment is available.
0 (disabled) or 1 (enabled)
This tunable helps defend against denial of service attacks on TCP by limiting the rate by which a RST segment is sent out. The only time this rate control should be disabled is when strict conformance to RFC 793 is required.