Codes
What is BLACKHORSE? It's a word used to encode and decode a set of numbers over a tactical radio net/freq when you don't have a military CEIOI available. It's used to send a unit's location (grid co-ordinates) without the enemy knowing what secret code network you're using. Here's how it works:
Word ---> B L A C K H O R S E
No. ---> 1 2 3 4 5 6 7 8 9 10To use, simply speak as if you're using a CEOI encode/decode book. Example:
"We will be located at Alpha-Bravo-Echo-Lima-Oscar-Hotel at Bravo-Echo-Echo-Echo"
Decoded, it's grid co-ordinates 31052276 at 1000 hours.
Simple, isn't it? But you don't have to stick to the one word BLACKHORSE as long as the letters in the word are not repeated twice and there's a total of 10 letters for the numbers 1-9 and the '0' is always used as the first number.
Try to make up your own unit code word or words to use. For example, Pathfinder, Rambosucks, Donkeyshit, BlackMother.
- 1st Write out the Alphabet on a piece of paper.
- 2nd Pick out a start letter. For this example, we'll use "k".
- 3rd Start at the letter k and directly under it, write the letter a, then b, and so forth until you've used up all the letters of the alphabet.
See Below
Letter--> A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
Q R S T U V W X Y Z A B C D E F G H I J K L M N O PTo send a coded message, you simply write out the message the same way you would write out a CEOI.
Example:
Message: Bring some beer to the patrol base.
Coded: rhydw iecu ruuh je jxu fqjheb rqiu.To identify and tell the other radio station you are encoding and decoding messages, simply say, "message follows AQ". This will let the other station know you are using a non CEOI coded message and that the first coded letter "A", will begin under the letter "Q".
Now, all you have to do is brief your troops on how to use this method.
Enigma is considered a simple letter substitution. One letter for one letter in a randomized alphabet key. The message is encrypted by passing it through a letter substitution three times then reversed and substituted three more times.was a letter substitution cypher.
The thing that made Enigma so tough to crack was the massive amount of possible randomized alphabets you could use to encrypt the message.
The Vignere cypher uses the simple grid of course, but the key that you state is so easy is for all intents and purposes impossible to figure out. If the person were stupid enough to use the keyword "it" you would have a doubled substitution that would take a minimum of six hours at 1 try per second. That assumes you would try the word "it" as the key, though. Not knowing the key length, you 're looking at far more than six hours.
By using a key like "encyclopedia", you have twelve re-occuring substitutions....and there is *no* way to figure out the possible key length without running a dictionary program and trying every possible combination. You simply can't know the key length without trying every possible combination.
To make that message absolutely secure, run that encyphered message through a second key and perhaps a third.
The "Enigma Grid" is identical to the Vignere system but uses a randomized alphabet instead of the standard "a,b,c..." and is easily done by drawing a 26x26 grid and starting with the top left square you put in "A" then go down two and right one and put in "B" etc....you end up with an alphabet that is sufficiently mixed that the total chances of hitting on the right letter pattern are nil.
A randomized grid, a non-repeating eight letter key, and with four cycles, you are talking about 1 in 3.9e+32 chance of solving it.
The message takes ohhh, about ten mins to encrypt and the same amount of time to decrypt....but it *can't* be broken.
Beyond simple substitution of course, but like I said, ten mins with a pencil and paper and you can encrypt any message and have it be practically undecypherable.
A vignere cypher has a cyclic key - you have, say, an eight-character key word, and use a different substitution for every eighth character.
These are also trivial. Once you've figured out how to identify the key length, it's just eight simple substitution cyphers.
Enigma and other mechanical cyphers attempt to generate arbitrarily long key sequences, and don't quite manage it. But it puts them beyond what you can break with paper and pencil.
