Tuesday, May 3, 2016

Update on Case Wicher

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.


  1. Hi Christos

    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

    1. Yes but it also helped radio operators when some of the letters when not received correctly.

  2. Hi Christos

    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.

  3. 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.

    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.