If you are testing a SUT that cannot be part of a larger network (usually for security or logistical purposes), Direct Connections explains how to create a closed, local connection with Eggplant Functional.
Reverse VNC Connections
If you are unable to configure the firewall of a SUT to accept VNC connections, you can often open a reverse VNC connection, in which the SUT initiates the VNC connection and the Eggplant Functional computer accepts it.
Connecting with a KVM Switch
If you are unable to install a VNC server on the SUT due to security concerns or lack of VNC server availability, Connecting with a KVM Switch is a good alternate method.