I want to know the answer to the following question:
What are machines that operate with no contact to the outside world called?
All the background I'm provided with is that "Even machines that operate as a closed system (i.e., with no contact to the outside world) can be eavesdropped upon via monitoring the faint electro-magnetic transmissions generated by the hardware; TEMPEST is a specification by the NSA referring to these attacks.". Is that enough to answer the question?
Answer: yes