3 ms·

Uneducated guess - the ability to quickly completely and utterly obliterating the pad would probably be a much more significant concern than space or weight. A

by lb1lf 6y ago

Uneducated guess - the ability to quickly completely and utterly obliterating the pad would probably be a much more significant concern than space or weight. After all, you don't want your cipher desk, OTP and all to be overrun by opfor just as you are encoding "we are being boarded!"

TheAdamAndChe 6y ago
The nice thing about a OTP is that it's only used once, unlike a typical cipher. If pads are lost, well that's fine because they weren't going to be used with anyone else.
- lb1lf 6y ago
  True, but with the (used) pads you can reconstruct past messages. (Provided you intercepted those, that is.)
  - jandrese 6y ago
    Sure, but it's also easy to have a system where the pad is destroyed after it is used. This would help insure that nobody messes up and uses the same bits twice as well.
- _wldu 6y ago
  You can also have a separate set of pads that decrypt the messages to something entirely different from the real messages. I'm not aware of another crypto system that allows for this. Here's an example: $ padder -d -m c2wrbumxvj8gob34mxn46pxg29a6kxnwfhcaam3en-hr-2v -p ryxrvqnlhz04icqq6eg56cuhg10vlx5dff3ba44wg6ic-kd PlainText: we-are-moving-north-and-will-attack-at-the-pass $ padder -d -m c2wrbumxvj8gob34mxn46pxg29a6kxnwfhcaam3en-hr-2v -p zifs6d9dgk36k94m9d5x77jhj277ip59gw9btmv4j7in-kc PlainText: our-group-fled-south-to-the-city-we-sailed-east
todd8 6y ago
In World War II, navy code books were bound with lead covers to make it easy to safely jettison the books overboard if necessary. Such code books where a bit like dictionaries containing random alphanumeric sequences for each useful plaintext word. This was then subjected to an additional layer of encipherment. Such a code was generally beyond the ability of foes to break. Many years past the battle of Midway, it was finally revealed that the US had broken the Japanese Navy code known as “Purple”, explaining the United States lucky outcome in that important battle. I believe it was through a combination of obtaining one of the code books and cryptanalysis.

by lb1lf 6y ago

TheAdamAndChe 6y ago

The nice thing about a OTP is that it's only used once, unlike a typical cipher. If pads are lost, well that's fine because they weren't going to be used with anyone else.

lb1lf 6y ago
True, but with the (used) pads you can reconstruct past messages. (Provided you intercepted those, that is.)
- jandrese 6y ago
  Sure, but it's also easy to have a system where the pad is destroyed after it is used. This would help insure that nobody messes up and uses the same bits twice as well.
_wldu 6y ago
You can also have a separate set of pads that decrypt the messages to something entirely different from the real messages. I'm not aware of another crypto system that allows for this. Here's an example: $ padder -d -m c2wrbumxvj8gob34mxn46pxg29a6kxnwfhcaam3en-hr-2v -p ryxrvqnlhz04icqq6eg56cuhg10vlx5dff3ba44wg6ic-kd PlainText: we-are-moving-north-and-will-attack-at-the-pass $ padder -d -m c2wrbumxvj8gob34mxn46pxg29a6kxnwfhcaam3en-hr-2v -p zifs6d9dgk36k94m9d5x77jhj277ip59gw9btmv4j7in-kc PlainText: our-group-fled-south-to-the-city-we-sailed-east

todd8 6y ago

In World War II, navy code books were bound with lead covers to make it easy to safely jettison the books overboard if necessary. Such code books where a bit like dictionaries containing random alphanumeric sequences for each useful plaintext word. This was then subjected to an additional layer of encipherment. Such a code was generally beyond the ability of foes to break. Many years past the battle of Midway, it was finally revealed that the US had broken the Japanese Navy code known as “Purple”, explaining the United States lucky outcome in that important battle. I believe it was through a combination of obtaining one of the code books and cryptanalysis.