Posted by: Anonymous Coward
on August 12, 2004 01:46 AM
Port knocking by UDP can't work. Either the author doesn't understand TCP/IP at all, or he didn't really think about it.
UDP is *not* a reliable communication protocol. Packets can get lost or be delivered in a different order than they were sent. If the server must receive the exact same data that you are sending (in this case, the exact same sequence of knocks), you *must* use TCP. That's exactly what it's been designed for.