... Description of document: A History of U.S. Communications Security (Volumes I and II); the David G. Boak Lectures, National Security Agency, 19... ...h respect to any loss or damage caused, or alleged to have been caused, directly or indirectly, by the information provided on the governmentattic.o... ...o your request of 23 December 2007 to have A History of U.S. Communications Security (2 volumes) by David G. Boak, Fort George G. Meade, MD National S... ... and second: trarllpo.ition-keeping our original meaniDgful text, but jumbUng the pom:;oM of our words or letters or digits so they no ORIGINAL 11 !~ ... ...tion of one value for another. These range from systems whose security stems from a few letters, words, or digits memorized in somebody's head, throug... ...of them. Let's look at a couple of codes: 1. The simplest kind, called a "one-part code", simply lists the plaintext meanings alphabeti­ cally (so tha... ...size) of an intelligencesi~ such as one's voice, at fixed intervals of time determined by a high frequency pulse train, then transmitting the values t... ...·~1-· ..~ y, ac m • w en e OVl pu a rat Ir compre eDSlve 88t 0 5 n . or the suppression of radio frequency interference., were those standards much mo... ...velop some interim suppreBlicm measures for their product liDes, and the Committee published two lists: one contaiDing equipments which were for· bidd...

...This publication consists of a series of lectures prepared and given to interns and other employees by Mr. David G. Boak in 1966. Mr. Boak is uniquely qualified to discuss the history of the US COM_SEC because he has participated significantly in most aspects of its modern development over the past twenty years....