Curtains for the Tempest threat?
Intell IT blog entry
Concern about remote eavesdropping on intelligence community computers by intercepting unintentional emissions from the equipment surfaced in the general press in the 1990s, followed by a series of news stories generally debunking the security risks.
Some practitioners reportedly said that although eavesdropping on a computer in an adjacent hotel room, for example, might be feasible, the resulting data probably would be fragmentary or worthless. Anecdotes about long-distance eavesdropping using Tempest technology from, say, hundreds of yards away, were bunk, those sources said.
It does seem clear that the level of advertising and publicity surrounding Tempest technology has quieted dramatically.
Some practitioners point to the notion that Tempest is not an acronym for an eavesdropping technology but rather a description of ways to foil such eavesdropping. They cite the rarely used expansion of the acronym to support their views: Telecommunications Electronics Material Protected from Emanating Spurious Transmissions.
However, a technology shift since Tempest's heyday in the mid-1990s might have severely restricted the opportunities for would-be eavesdroppers. Cathode ray tube (CRT) displays have been progressively replaced by various types of flat screens, which appear comparatively resistant to such eavesdropping.
On the other hand, spurious emissions can also come from other components.
Whatever the status of these technology developments, an unobtrusive slice of the federal information technology vendor community has been marketing Tempest services and equipment for two decades or more. To follow up, check with companies such as Tempest
Comments on the unintentional electronic emissions of CRT monitors as compared with flat-screen monitors are welcome.
Posted by Wilson P. Dizard III on May 27, 2008 at 9:39 AM