Block ciphers work in a way similar to polyalphabetic ciphers, with the exception that a block cipher pairs together two algorithms for the creation of ciphertext and its decryption. ... Each algorithm uses two inputs: a key and a “block” of bits, each of a set size.

Which cipher is Polyalphabetic?

A polyalphabetic cipher is any cipher based on substitution, using multiple substitution alphabets. The Vigenère cipher is probably the best-known example of a polyalphabetic cipher, though it is a simplified special case.

Are block ciphers permutations?

The idealized abstraction of a (keyed) block cipher is a truly random permutation on the mappings between plaintext and ciphertext.