This looks like an interesting idea for our lab connectivity start up:
Random connections over the Internet, secured by x509 certificates, with the payload format unspecified. Assuming we control the certificates, we can be confident that our connections are secure from others and from the right computers.
We would use HL7 to encode the payload, of course. But this gives us a validated and accepted model for transactions in a cloud-based environment. Interesting. I feel a proof-of-concept project coming, probably built on Amazon Web Services.
This architecture also lets us circle back to this at some point down the road: