[ARC5] WWII One Time Pads

[Robert Eleazer]

I can't answer John's questions, but the book "Between Silk and Cyanide" covers the challenge of encoding and decoding agent messages.

The title comes from a point once made by the author that the one time pads needed to be printed on (precious) silk so to enable their concealment by agents inside their clothing.  The choice was between giving an agent his one time pad printed on silk or giving him a cyanide pill.

Before one time pads they used poem codes. An agent memorized a poem and told the people in England who he would communicate with what that poem was.  Then he just wrote the poem down when he needed to send a message and put "1" for the first letter and "2" for the next and so on until the entire alphabet was encoded by numbers.  Of course, all the enemy had to do was guess what the poem was, and since the letter "e" is the most common one in the English language, all they had to do was see which number in the radio message was used the most often and work from there.

Wayne