We embed this in in our core image, prior to capture. And VNC remote assistance can be enabled through the Sharing control panel in System Preferences. If you're managing from a Mac, you can use Remote Assistance or other tools, if your network allows. We choose to set a password for remote assistance, and VNCViewer, and understand that sessions in VNC depend on local screen sessions. If someone is logged in to their Mac, and you remote, then you are presented with a login screen and open a separate session without them knowing. If you have them log off, then VNC will share their session, so you can watch what they are doing and interact. Keep in mind I am working on a LAN.
SSH is a pain, Why is SSH a pain? It requires the generation of certs that will allow authentication for SSH sessions. We use WinSCP and Putty to allow sessions from PCs, but the current OS X architecture is making problems now. There is a bunch of great information in the Parallels for Mac Management Admin Guide and the web about doing this.
Last edited: Jun 22, 2016