Tool to decrypt/encrypt with Vernam (One Time Pad Vigenere). Vernam cipher is a particular case of Vigenere cipher where the key is as long as the text, which render useless any cryptanalysis attempt.
Vernam Cipher (One Time Pad Vigenere) - dCode
Tag(s) : Poly-Alphabetic Cipher
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Vernam Cipher (One Time Pad Vigenere)
Vernam (Vigenere) Cipher Decoder
Vernam (Vigenere) Encoder
Tool to decrypt/encrypt with Vernam (One Time Pad Vigenere). Vernam cipher is a particular case of Vigenere cipher where the key is as long as the text, which render useless any cryptanalysis attempt.
Answers to Questions
How to encrypt using Vernam cipher?
The Vernam Chiffre uses the Vigenere encryption method but using a key at least as long as the plain text.
Example: To encrypt DCODE, a key of at least 5 letters is needed (KEYWORD, PASSWORD, etc).
If the key is not long enough, it will be repeated, as in the Vigenere cipher, but this introduces a cryptographic weakness in the message.
How to decrypt Vernam cipher?
Decryption is also identical to Vigenere decryption method.
How to recognize Vernam ciphertext?
The Vernam cipher message has an indice of coincidence close to a random text.
The disposable mask name is also given to this cipher.
How to decipher Vernam without key?
If the key length is as long as the text length, then no cryptanalysis method can crack Vernam.
When Vernam cipher have been invented ?
First example have been found at the end of the 19th century and Vernam described it in 1917.
Source code
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Questions / Comments
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