From the clear text, NONSTOP appears to refer to
One of the Tempest FOIA docs NSA released recently concerns NONSTOP, a term whose definition is classified as SECRET. About half of the document, NACSEM 5112, "NONSTOP Evaluation Techniques," has been redacted, and we'll publish it soon. protection against compromising emanations of cryptographic systems, and maybe in particular radio crypto systems. Another document refers to NONSTOP testing and protection being especially needed on vehicles, planes and ships. We've been unable to retrieve more than a few words from the redacted portions (by use of xerography to reveal text below the overwrites), and would appreciate any leads on what NONSTOP means. Joel McNamara has been searching for NONSTOP info for some time: http://eskimo.com/~joelm/tempest.html We would also like to learn more about covert surveillance by "resonance" technology. Peter Wright, in Spycatcher, provides most interesting anecdotes about this. He writes of remotely "radiating" specially-designed objects in a space to pick up signals, and tells of several covert operations in which MI5 used this method. Wright also describes the use of supersensitive microphones to pick up the daily setting of rotors on cryptomachines of the time, in particular the Hagelins made by CryptoAG. This loops back to NONSTOP and the question of what may be the signatures and compromising emanations of today's cryptosystems which reveal information in ways that go beyond known sniffers -- indeed, that known sniffers may divertingly camouflage. Along this line I mention for the nth time that the National Academy of Science 1996 CRYPTO report, which advocated loosening crypto controls, also recommended increased funding for other surveillance technologies that have never been identified, although Carnivore may be one such, along with keyboard sniffers and who knows what else that has been passed to domestic law enforcement by the intelligence agencies to crack crypto protection.