From: sven.schott@... Date: 2005-12-21T13:17:48+09:00 Subject: Re: Port Knocking Port knocking is normally TCP and UDP although there are a number of implementations with ICMP. It wouldn't be much harder to do with UDP but that means that a client would be required as I don't know of any(standard) unix programs that can send custom TCP or UDP packets. I'm looking at fixing a few of the things in the script like the timeout so I might throw in an option for TCP/UDP and a small client.