Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!henry From: henry@utzoo.UUCP (Henry Spencer) Newsgroups: net.micro Subject: Re: Zenith-U.S. Government Contract Message-ID: <4457@utzoo.UUCP> Date: Sat, 13-Oct-84 21:23:50 EDT Article-I.D.: utzoo.4457 Posted: Sat Oct 13 21:23:50 1984 Date-Received: Sat, 13-Oct-84 21:23:50 EDT References: <3365@ecsvax.UUCP> Organization: U of Toronto Zoology Lines: 17 > Does anybody know anything about the "Tempest" specs and what they mean? The "Tempest" specs are a tough set of specs on exactly how much of the system's electromagnetic activity can be detected at specific (short) ranges. The intent is not protecting other systems from interference, but protecting secret data against electromagnetic eavesdropping. In theory, you can get a nice readout of a computer's internal activity by monitoring its radio emissions; the Tempest specs aim at cutting down the radiation to the point where such snooping is utterly impractical. The details of the Tempest specs are secret (!). You can't even get a look at them unless the government agrees that you are a potential supplier of Tempest-qualified gear, and you meet the other assorted prerequisites for a suitable level of security clearance. -- Henry Spencer @ U of Toronto Zoology {allegra,ihnp4,linus,decvax}!utzoo!henry