Endre Szabo <syslog-ng at end.re> writes: > Here's a proof of concept of DNS based port knocking. Firewall opens > up port of SSHd for 10 seconds after nameserver answering to a > predefined DNS query. It uses pattern db and netfilter only. > > http://vimeo.com/endreszabo/dns-portknocking This is seriously wicked. -- |8]