Breaking Fish Codes at Bletchley Park

This book is an edition of the General Report on Tunny with commentary that clarifies the often difficult language of the GRT and fitting it into a variety of contexts arising out of several separate but intersecting story lines, some only implicit in the GRT. 

• Explores the likely roots of the ideas entering into the Tunny cryptanalysis
• Includes examples of original worksheets, and printouts of the Tunny-breaking process in action
• Presents additional commentary, biographies, glossaries, essays, and bibliographies

James A. Reeds is an applied mathematician and is currently on the research staff at the Center for Communications Research, Princeton, NJ.

Whitfield Diffie is best known for his 1975 discovery of the concept of public key cryptography. Since 1993, he has worked largely on public policy aspects of cryptography. His position in opposition to limitations on the business and personal use of cryptography has been the subject of articles in the New York Times and programs on networks such as CNN.

J.V. Field, an Honorary Visiting Research Fellow in the Department of History of Art at Birkbeck, University of London, is now a historian of science but in the 1960s worked as a computer programmer.