Real time networking - What do you use?

Hi all,

I am preparing a presentation on RT networking and RT communication. Therefore I would like to ask you what kind of networking you use for your distributed RT applications. I am interested in both hardware (e.g. Ethernet, CAN, wireless (?) etc.) and software / protocols (qnet, …) used.
Any links to related work would also be helpful.

Thanks a million,

Smee