The following paragraph has been added in Case ‘Wicher’ – Information from the war diary of Inspectorate 7/VI.
The war diary of Inspectorate 7/VI, in the report of February 1942, says that an investigation of captured Polish files revealed deciphered German radio messages and this material was forwarded to Inspectorate 7/VI to clarify if the compromise was a result of treason or deciphering and if it was the latter to identify the compromised cipher system.
Thinking about Wicher. Was not the double enciphering of the same 3 letters a highly insecure practice? I mean, surely any mathematical crypto types would have advised against it
Yes but it also helped radio operators when some of the letters when not received correctly.Delete
I have been reading some u boat related books. I see Bonatz in ca 1968 (after publication of a book on enigma by one of the poles) said he thought it was impossible for them to have broken enigma. I wonder why he said that? One assumes he knew of Wicher background.
On the other hand I see that immediate post war interviews revealed that many of the (non naval officer ) crypto personnel had long felt that enigma was not secure - eg Tranow.
Also, reading a u boat officer's book, struck me how bad Doenitz' radio procedures were - too much unnecessary traffic leading to hf/df. But also many messages like "attacked by aircraft", "attacked by aircraft , sinking". Sent at the same time as the attack - easy crib material surely.ReplyDelete
Slightly unrelated, Venona. Interesteing that a one time pad system, even with computer attacks, massive resources and time and benefit of using some of the pads more than once, only a small % of materiel was decrypted.
One time pad system better than a machine for fairly short messages.