General Discussions
This is the place to discuss general issues related to the U-boat war or the war at sea in WWII.
RE: One time codes
Posted by:
Sean
()
Date: June 18, 2001 10:56AM
<HTML>I don\'t think that there was much possibility of large-scale usage of one-time codes.
For maximum security a one-time pad has only two copies - in this case one copy would be held back at base and one on the boat. Before setting sail, there would have to be sufficient volume of pads on board for a long voyage (several months, remember).
Consider how you would assemble a wolfpack securely? Each message from HQ would have to be retransmitted for each boat using a different pad. How would the boats communicate with each other safely to coordinate an attack? Would each boat have a shared pad to talk to every other boat (vulnerable to pinches, same as Enigma)? Or would all messages be delayed by retransmission through HQ? What would this mean for efficiency?
Consider also the cost of producing truly random one-time pads. Mathematicians and cryptanalysts drive themselves insane now trying to produce truly random sequences properly.
But - what about the weaknesses in the employment of Enigma that made it so much easier to break?
- Retransmission of verbatim messages over multiple code nets (any of which may have been compromised),
- large monologues from command (allowing the codebreakers a greater volume of text to work with),
- occasional re-use of keys (user error, training problems),
- the constant refusal of command to believe that their codes had been broken or captured (and not fixing them or issuing new keys),
- a much more active analysis of the codes in use and operational events leading to a more reactive update of codes (command managed to convince itself all was well despite evidence to the contrary)
These are simple things that could have easily been fixed and improved the whole system.
I\'m not saying that it wouldn\'t have been broken (faster tabulating machines, more pinches, there will always be human lapses), but it needn\'t have been as easy (?!) as it was.
One time codes are very secure, but they are hard to produce in volume properly - automating them really just reduces you to a machine generated system and as Enigma shows, machine systems are vulnerable.
Anyway, a couple of ideas to think about.
Cheers,
Sean
(just interested in crypto and not a cypherpunk by any means, but maybe I\'ve read Cryptonomicon and some other books a few too many times ;-)</HTML>
For maximum security a one-time pad has only two copies - in this case one copy would be held back at base and one on the boat. Before setting sail, there would have to be sufficient volume of pads on board for a long voyage (several months, remember).
Consider how you would assemble a wolfpack securely? Each message from HQ would have to be retransmitted for each boat using a different pad. How would the boats communicate with each other safely to coordinate an attack? Would each boat have a shared pad to talk to every other boat (vulnerable to pinches, same as Enigma)? Or would all messages be delayed by retransmission through HQ? What would this mean for efficiency?
Consider also the cost of producing truly random one-time pads. Mathematicians and cryptanalysts drive themselves insane now trying to produce truly random sequences properly.
But - what about the weaknesses in the employment of Enigma that made it so much easier to break?
- Retransmission of verbatim messages over multiple code nets (any of which may have been compromised),
- large monologues from command (allowing the codebreakers a greater volume of text to work with),
- occasional re-use of keys (user error, training problems),
- the constant refusal of command to believe that their codes had been broken or captured (and not fixing them or issuing new keys),
- a much more active analysis of the codes in use and operational events leading to a more reactive update of codes (command managed to convince itself all was well despite evidence to the contrary)
These are simple things that could have easily been fixed and improved the whole system.
I\'m not saying that it wouldn\'t have been broken (faster tabulating machines, more pinches, there will always be human lapses), but it needn\'t have been as easy (?!) as it was.
One time codes are very secure, but they are hard to produce in volume properly - automating them really just reduces you to a machine generated system and as Enigma shows, machine systems are vulnerable.
Anyway, a couple of ideas to think about.
Cheers,
Sean
(just interested in crypto and not a cypherpunk by any means, but maybe I\'ve read Cryptonomicon and some other books a few too many times ;-)</HTML>
| Subject | Written By | Posted |
|---|---|---|
One time codes
|
bernardZ | 06/17/2001 11:26AM |
|
RE: One time codes
|
Walter M. | 06/17/2001 05:34PM |
|
RE: One time codes
|
Sean | 06/18/2001 10:56AM |
|
RE: One time codes
|
Bernardz | 06/22/2001 02:40PM |