I'm still being not clear of what you mean by:

>with SSH, the server will send a version string upon connection (and expects the client to do the same).

Say for example if I do:

   ssh some.machine.com

I'm (being the client ) call the ssh port ( server ) running on the some.machine.com, right? If thats the case, client is who starting the conversation right?

Correct me if I'm wrong.