[44net] security reminder

Folks, Please remember that when you set up a host, computer, or device on the AMPRNet, it is exposed to the big bad evil environment of the Internet without any form of protection such as a firewall or traffic filter, UNLESS YOU PROVIDE IT. In recent days we've had a some more complaints about systems being used as DNS amplification attack vectors, others as having been compromised and turned into a spam bot, and so on. I wish these were unusual events, but they're not rare enough. Yes, you're being thrown into the network security swamp, and having to learn to swim while trying to keep your head above water. Please be careful. Practice safe networking! - Brian