Hi
I was following this thread since the beginning and maybe I can add my 2 cents comment about transmitting information safely over ethernet.
One way to get safe and reliable transmission is using RTP protocol and a mix of TCP and UDP packet.
You basically send your normal packet using UDP (fast but unreliable) but since RTP packets contain a timestamp in every packet, in case you are missing one packet you can always request it using TCP.
This method requires a bigger buffer on the client side and a circular buffer on the server side but in most case it allow you to sync multiple system using the timestamp and have a reliable transmission.
This is used in some IPTV system in order to get reliable transmission of multicast UDP packet.
I don't say it's easy to put in place but that a way to achieve the reliability and allw the client side to "know" when the information is missing and possibly avoid any "dangerous" behaviour.
Forgive my incoherence, I'm not a laser!