On Thu, Aug 10, 2017 at 10:24 PM, Bill Frantz <fra...@pwpconsult.com> wrote: > I found an interesting book in a Sydney, Australia airport book stall: > > Code Breakers > Inside the shadow world of signals intelligence in Australia's two Bletchley > Parks > Craig Collie > First published in 2017 by: > Allen & Unwin > 83 Alexander Street > Crows Nest, NSW 2065 > Australia > <www.allenandunwin.com> > ISBN 978 1 74331 210 0 > > This book describes the signals intelligence efforts in Australia during > WWII. It goes into detail about the politics, personalities, code breaking, > and traffic analysis used in some of the epic battles in the south Pacific. > It describes the early use of IBM tabulating equipment in code breaking. It > gives enough detail about the structure of the Japanese codes so the reader > can appreciate the effort needed to break them and re-break them after they > were changed. > > A brief description of the typical code structure: First the messages was > converted to numbers using a code book which took words or phrases as input. > Then "additive tables" were used like a one time pad to scramble the output > of the code book for transmission. Since the additive tables were reused > many times, there were obvious security issues, although these issues don't > seem to have been the major way the codes were actually broken. > > Traffic analysis based on the strength and direction of radio signals > allowed prediction of air attacks without being able to read the messages, > although since the airplane codes were designed for easy use in the air, > they were relatively easy to break. > > The book is also a fun read. Recommended. > > Cheers - Bill
The Secret Code-Breakers of Central Bureau: how Australia’s signals-intelligence network helped win the Pacific War - David Dufty infohash:C48528487723B42DB5C3A019179AC0CE90829B4C Code Warriors_ NSA's Code Breakers and the Secret Intelligence War Against the Soviet Union by Stephen Budiansky infohash:B2E01DC6AE6607D7BF88D6B504802DB677C563EE Crypto Anarchy, Cyberstates, and Pirate Utopias - Peter Ludlow infohash:DE1B89F605AFB3896D9153BD27F691B009F56092