BICTCP_B
/ BICTCP_B;
ca->cnt = (cwnd * smooth_part) / BICTCP_B;
if (cwnd < ca->last_max_cwnd + BICTCP_B)
ca->cnt = (cwnd * smooth_part) / BICTCP_B;
else if (cwnd < ca->last_max_cwnd + max_increment*(BICTCP_B-1))
ca->cnt = (cwnd * (BICTCP_B-1))