All you need is the hostname of the machine you want to install the agent on, its SSH port that it's listening to (default is 22) and the credentials of the user who will install (and run) the JON agent.
You can install, start, and stop the JON agent from this UI mechanism. You can also use it to get the status of any JON agent that might be installed as well and even attempt to find if and where an agent may be installed on the remote box.
Here's a snapshot of the UI page after I just successfully remote installed a JON agent:
