Table of Contents

Communications and Sigint.- Japanese Expansion 1895-1941.- The GCCS 1919-1941.- William Friedman and the US Army.- Early American Naval Sigint.- Developments in Australia.- Preparedness for Attack?- Major Technical Encryption Systems.- JN-25 and its Cryptanalysis.- Using Common Book Groups.- Recovery of a Code Book.- Breaking Additive Systems.- Making Additive Systems Secure.- Redundant Encryption.- The Scanning Distribution.- Ciphers and the Submarines.- Central Bureau 1942-1945.- Organisation and Reorganisation.- Security, Censorship and Leaks.- Conclusion.- From Pearl Harbor to Midway.- Guadalcanal and Papua.- Rabaul and the Philippines.

Reviews

“It is an important contribution to both the history of the war and the history of cryptanalysis development, as well as an interesting text on techniques of cryptography and cryptanalysis. … The book is well written and reads well. It is well referenced with myriad footnotes. I admire and recommend it.” (Mordechai Ben-Menachem, Computing Reviews, April, 2015)