[asterisk-users] Using Firewall to protect Asterisk

[CDR]

I need to keep out all connection from 5 countries, which originate
most of the Denial of Service attacks. The entries are
around 9000 if used as xx.xx.0.0/16. I heard that there is a smarter
way to do this by using User Tables in iptables, that will keep the
speed equal to LOG(x). I already tried using  a straight list and it
kills the box. Unless a smarter way us found, there is no way to use
iptables.

Federico