Saturday, October 9, 2010

Telephone Keypad Cipher

If you’ve every noticed closely on you telephone keypad, each number 2-9 matches up with a letter.
2 = A, B, or C
3 = D, E, or F
4 = G, H, or I
5 = J, K, or L
6 = M, N, or O
7 = P, Q, R, or S
8 = T, U, or V
9 = W, X, Y, or Z

Here is an example of a telephone keypad cipher
Message: “x marks the spot”
Cipher: 9627578437768

Telephone keypad ciphers can be a bit tricky as each number could still represent up to 3 different letters. For example in the above cipher, if someone was trying to decipher it, they may think the first letter in the message was “W” instead of “X” since 9 could represent “W”, “X”, “Y” or “Z”

Another way to use the Telephone Keypad Cipher is to use it to encipher a number message. A problem here is that the numbers 1 and 0 are not represented so characters would have to be created to represent those numbers.

An example of using a telephone keypad cipher to encipher your locker combination
Combination: 23-45-37
Cipher: ADHLER


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