Question

Difference between monoalphabetic and polyalphabetic cipher in tabular form

Answer 1

Explanation:

Viva Differences

Monoalphabetic Cipher Vs. Polyalphabetic Cipher: 5 Basic Difference Plus Example

Learn the basic difference between monoalphabetic cipher and polyalphabetic cipher: The basis of comparison include:Description, alphabetic character of plaintext, relation between characters,what it includes and dependency.

The Differences

A monoalphabetic cipher is one where each symbol in the input (known as the ‘’plaintext’’ is mapped to a fixed symbol in the output (referred to ciphertext). Polyalphabetic cipher is any cipher based on substitution, using multiple substitution alphabets.

In monoalphabetic Cipher, once a key is chosen, each alphabetic character of plaintext is mapped onto a unique alphabetic character of a ciphertext. On the other hand, in polyalphabetic cipher, each alphabetic character of plaintext can be mapped onto ‘’m’’ alphabetic characters of a ciphertext.

In monoalphabetic Cipher, the relationship between a character in the plaintext and the characters in the ciphertext is one-to-one, whereas in Polyalphabetic Cipher, the relationship between a character in the plaintext and the characters in the ciphertext is one-to-many.

Monoalphabetic Cipher includes additive, multiplicative, affine and monoalphabetic substitution cipher. On the other hand, Polyalphabetic cipher includes Autokey, Playfair,Roto, One-time pad, Enigma cipher and Vigenere.

For a stream cipher to be a monoalphabetic cipher, the value of ki does not depend on the position of the plaintext character in the plaintext stream. On the other hand, for a stream to be a polyalphabetic cipher, the value of id does not depend on the position of the plaintext stream.

The Difference Between Monoalphabetic Cipher and Polyalphabetic Cipher in Tabular Form

BASIS OF COMPARISON MONOALPHABETIC CIPHER POLYALPHABETIC CIPHER

Description A monoalphabetic cipher is one where each symbol in the input (known as the ‘’plaintext’’ is mapped to a fixed symbol in the output (referred to ciphertext). Polyalphabetic cipher is any cipher based on substitution, using multiple substitution alphabets.

Alphabetic Character of Plaintext In monoalphabetic Cipher, once a key is chosen, each alphabetic character of plaintext is mapped onto a unique alphabetic character of a ciphertext. In polyalphabetic cipher, each alphabetic character of plaintext can be mapped onto ‘’m’’ alphabetic characters of a ciphertext.

Relation Between Characters In monoalphabetic Cipher, the relationship between a character in the plaintext and the characters in the ciphertext is one-to-one, In Polyalphabetic Cipher, the relationship between a character in the plaintext and the characters in the ciphertext is one-to-many.

What it Includes Monoalphabetic Cipher includes additive, multiplicative, affine and monoalphabetic substitution cipher. Polyalphabetic cipher includes Autokey, Playfair,Roto, One-time pad, Enigma cipher and Vigenere.

Dependency For a stream cipher to be a monoalphabetic cipher, the value of ki does not depend on the position of the plaintext character in the plaintext stream. For a stream to be a polyalphabetic cipher, the value of id does not depend on the position of the plaintext stream.

Examples