What is TEMPEST?
Let's start with the definition From the learning Company and PC Magazine we get one of the more solid and concrete definitions as follows: http://www.pcmag.com/encyclopedia_term/0,2542,t=TEMPEST&i=52733,00.asp
"Definition of: TEMPEST
Refers to external electromagnetic radiation from data processing equipment and the security measures used to prevent them. Almost all electronic equipment emanates signals into free space or surrounding conductive objects such as metal cabinets, wires and pipes. Equipment and cables that meet TEMPEST requirements have extra shielding in order to keep data signals from escaping and being picked up by unauthorized listeners. It is also possible to use TEMPEST software that generates sufficient electronic noise to mask meaningful radio-frequency emissions. "
They go on in a paragraph to say it was a code name for a government project in the 60's and that they aren't sure of the exact acronym. However from what I understand it is the second of their two choices there "...Transient Electro Magnetic Pulse Emanation Standard."
An excellent article about how TEMPEST has been implimented is :
The Tempest over Leaking Computers
by Harold Joseph Highland http://cryptome.org/tempest-leak.htm
"Harold Joseph Highland is Distinguished Teaching Professor Emeritus of the State University of New York and a Fellow of the Irish Computing Society. He is editor-in-chief of Computers & Security, the official journal of IFIP Technical Committee 11. As managing director of CompuLit Inc., he heads the organization's Microcomputer Security Testing Laboratory. He writes regularly for several computer and law journals in England, Germany, Australia, Italy, and the States. He was Fulbright Professor of Computer Science at Helsinki University of Technology and the Medical School of the University of Helsinki in 1970-1971. He is the author of over 200 technical articles and some 30 books several of which have been translated into Japanese, German, French, Dutch, Finnish, and Russian. He received his Ph.D. in 1942 B.C. (before computing) while serving with the USAAF during World War II, and learned computing by a "hands-on-approach" while he was dean of the Graduate Business School at Long Island University in 1958.
In the spring of 1985 the British public viewed the first demonstration of eavesdropping on a computer's electromagnetic radiation. BBC's "Tomorrow's World" ran a five-minute demonstration on television. The program showed a long shot of a van parked in front of a building in London and faded to a close-up inside the van where a document was displayed on a television screen. The commentator noted that the van's equipment had to scan numerous terminals and documents inside the building before finding one on the upper floors that was suitable to show on the air. At no time did the program identify the building because it is as well known in England as the U.S. Capitol is in the States. The London building in front of which the van was parked was New Scotland Yard...." continued here.
Now for a couple of time lines:http://cryptome.sabotage.org/tempest-time.htmhttp://www.caslon.com.au/surveillanceprofile15.htm
Wikipedia Defines TEMPEST as follows :http://en.wikipedia.org/wiki/TEMPEST
"TEMPEST is a codename referring to investigations and studies of compromising emanations (CE). Compromising emanations are defined as unintentional intelligence-bearing signals which, if intercepted and analyzed, disclose the information transmitted, received, handled, or otherwise processed by any information-processing equipment.
Compromising emanations consist of electrical or acoustical energy unintentionally emitted by any of a great number of sources within equipment/systems which process national security information. This energy may relate to the original message, or information being processed, in such a way that it can lead to recovery of the plaintext. Laboratory and field tests have established that such CE can be propagated through space and along nearby conductors. The interception/propagation ranges and analysis of such emanations are affected by a variety of factors, e.g., the functional design of the information processing equipment; system/equipment installation; and, environmental conditions related to physical security and ambient noise. The term "compromising emanations" rather than "radiation" is used because the compromising signals can, and do, exist in several forms such as magnetic and/or electric field radiation, line conduction, or acoustic emissions.
The term TEMPEST is often used broadly for the entire field of Emission Security or Emanations Security (EMSEC). The term TEMPEST is neither an acronym nor abbreviation: it is a randomly selected codeword or coverword for a process which is sensitive from a security standpoint.  Various backronyms have been suggested, laconically, for the term, (TEMPEST) including "Transmitted Electro-Magnetic Pulse / Energy Standards & Testing" "Telecommunications ElectroMagnetic Protection, Equipments, Standards & Techniques", "Transient ElectroMagnetic Pulse Emanation STandard" and "Telecommunications Electronics Material Protected from Emanating Spurious Transmissions" or, jokingly, Tiny ElectroMagnetic Particles Emitting Secret Things....It goes on to name the US goverment and NATO act's relating to it and their future projects
 TEMPEST measurement standards
The US and NATO TEMPEST standards define three levels of protection requirements:
NATO SDIP-27 Level A (formerly AMSG 720B) and USA NSTISSAM Level I
"Compromising Emanations Laboratory Test Standard"
This is the strictest standard for devices that will be operated in NATO Zone 0 environments, where it is assumed that an attacker has almost immediate access (e.g., neighbour room, 1 m distance)
NATO SDIP-27 Level B (formerly AMSG 788A) and USA NSTISSAM Level II
"Laboratory Test Standard for Protected Facility Equipment"
This is a slightly relaxed standard for devices that are operated in NATO Zone 1 environments, where it is assumed that an attacker cannot get closer than about 20 m (or where building materials ensure an attenuation equivalent to the free-space attenuation of this distance)
NATO SDIP-27 Level C (formerly AMSG 784) and USA NSTISSAM Level III
"Laboratory Test Standard for Tactical Mobile Equipment/Systems"
An even more relaxed standard for devices operated in NATO Zone 2 environments, where attackers have to deal with about 100 m worth of free-space attenuation (or equivalent attenuation through building materials)
Additional standards include
NATO SDIP-29 (formerly AMSG 719G)
"Installation of Electrical Equipment for the Processing of Classified Information"
This standard defines installation requirements, for example in respect to grounding and cable distances.
"NATO Zoning Procedures"
Defines an attenuation measurement procedure, according to which individual rooms within a security perimeter can be classified into Zone 0, Zone 1, Zone 2, or Zone 3, which then determines what shielding test standard is required for equipment that processes secret data in these rooms.
All these documents remain classified and no published information is available about the actual emission limits and detailed measurement procedures that they define. However, some very basic TEMPEST information has not been classified information in the United States since 1995. Short excerpts from the main U.S. TEMPEST test standard, NSTISSAM TEMPEST/1-92, are now publicly available, but all the actual emanation limits and test procedures have been redacted from the published version. A redacted version of the introductory TEMPEST handbook NACSIM 5000 was publicly released in December 2000. Equally, the NATO standard SDIP-27 (before 2006 known as AMSG 720B, AMSG 788A, and AMSG 784) is still classified.
 TEMPEST certification
The information-security agencies of several NATO countries publish lists of accredited testing labs and of equipment that has passed these tests:
BSI German Zoned Products List
CESG directory of infosec assured products – Section 12: TEMPEST
NSA TEMPEST Endorsement Program
The United States Army also has a TEMPEST testing facility, as part of the U.S. Army Information Systems Engineering Command, at Fort Huachuca, Arizona. Similar lists and facilities exist in other NATO countries.
TEMPEST certification must apply to entire systems, not just to individual components, since connecting a single unshielded component (such as a cable) to an otherwise secure system could easily make it radiate dramatically more RF signal. This means that users who must specify TEMPEST certification could pay much higher prices, for obsolete hardware, and be severely limited in the flexibility of configuration choices available to them. A less-costly approach is to place the equipment in a fully shielded room.
 NONSTOP and HIJACK
Two related areas of emissions security, code named NONSTOP and HIJACK, remain classified.
NONSTOP is thought to involve potential compromising emissions from electronic systems when they are inadvertently irradiated by other radio signals, including ordinary mobile phones.
HIJACK may refer to protection measures against active attacks of this nature. Example attacks could be attempts to detect aircraft at long distance not only by their passive reflection of radar waves, but by harmonics of the radar frequencies created by non-linear junctions in the aircraft's electronics (antenna amplifiers, IF tuners, etc.), similar to the nonlinear junction detector techniques used in counter intelligence and TV-license enforcement to detect and locate receivers.
 RED/BLACK separation
TEMPEST standards require "RED/BLACK separation", i.e. maintaining distance or installing shielding between circuits and equipment used to handle plaintext classified or sensitive information (red) and normal unsecured circuits and equipment (black), the latter including those carrying encrypted signals. Manufacture of TEMPEST-approved equipment must be done under careful quality control to ensure that additional units are built exactly the same as the units that were tested. Changing even a single wire can invalidate the tests.
 Correlated emanations
One aspect of TEMPEST testing that distinguishes it from limits on spurious emissions (e.g. FCC Part 15) is a requirement of absolute minimal correlation between radiated energy or detectable emissions and any plain text data that are being processed. It would stand to reason that this requirement holds in some form for other types of data as well.
It goes on to list Public research:
In 1985, Wim van Eck published the first unclassified technical analysis of the security risks of emanations from computer monitors. This paper caused some consternation in the security community, which had previously believed that such monitoring was a highly sophisticated attack available only to governments; van Eck successfully eavesdropped on a real system, at a range of hundreds of metres, using just $15 worth of equipment plus a television set. In consequence of this research such emanations are sometimes called "van Eck radiation", and the eavesdropping technique van Eck phreaking, although it is believed that government researchers were already aware of the danger, as the NSA published Tempest Fundamentals, NSA-82-89, NACSIM 5000, National Security Agency (Classified) on February 1, 1982. This technique is used as a plot point in Neal Stephenson's novel Cryptonomicon and in the Numb3rs Season 1 episode, 'Sacrifice'.
Markus Kuhn discovered several low-cost software techniques for reducing the chances that emanations from computer displays can be monitored remotely. With CRT displays and analogue video cables, filtering out high-frequency components from fonts before rendering them on a computer screen will attenuate the energy at which text characters are broadcast. With modern flat-panel displays, the high-speed digital serial interface (DVI) cables from the graphics controller are a main source of compromising emanations. Adding random noise to the less significant bits of pixel values may render the emanations from flat-panel displays unintelligible to eavesdroppers but is no secure method. Since DVI uses a certain bit code scheme for trying to transport an evenly balanced signal of 0 and 1 bits there may not be much difference between two pixel colours that differ very much in their colour or intensity. It may also be that the generated emanations may differ totally even if only the last bit of a pixel's colour is changed. The signal received by the eavesdropper does also depend on the frequency where he detects the emanations. The signal can be received on many frequencies at once and each frequency's signal differs in contrast and brightness related to a certain colour on the screen.
In October 2006 a group of opponents of electronic voting called "We don't trust voting computers" made a proof of concept how to hack the elections with tempest technique. There is also YouTube video available."
Now more than ever is a time when the ability of our government to watch every single person's entire life from birth to death depended solely on nothing more than a tiny bit of space on their massive computer storage array must a return to Constitutional Law happen.
It'd be one thing if we had a choice it's another when they arrest you when you try to stop them from watching you. Which I have several magazines that have articles discussing this sort of thing that seems to even be sucessfully edited out of google searches.Ron Paull for Prez 2k8! A chance for a return to the Constitution !