The correct response is Control Zone. Computer controls are installed and configured in a specific area to prevent attacks and include implementation of a protection device (a Faraday cage or white noise generation) that reduces the electrical emissions to thwart attempts to gather information through airwaves.

Tempest was the name of a classified (secret) U.S. government project to study (probably for the purpose of both exploiting and guarding against) the susceptibility of some computer and telecommunications devices to emit electromagnetic radiation (EMR) in a manner that can be used to reconstruct intelligible data. Tempest's name is believed to have been a code name used during development by the U. S. government in the late 1960s, but at a somewhat later stage, it became an acronym for Telecommunications Electronics Material Protected from Emanating Spurious Transmissions. Today, in military circles, the term has been officially supplanted by Emsec (for Emissions Security); however, the term Tempest is still widely used in the civilian arena.