Можно ли (и как) с помощью iptables защитица от флуда?

For example, let's limit the number of parallel HTTP connections made by a single IP address to 4 : # iptables -A INPUT -p tcp --syn --dport http -m iplimit --iplimit-above 4 -j REJECT

# iptables --list Chain INPUT (policy ACCEPT) target prot opt source destination REJECT tcp -- anywhere anywhere tcp dpt:http flags:SYN,RST,ACK/SYN #conn/32 > 4 reject-with icmp-port-unreachable