Question

Which of the following is not a type of poly alphabetic cipher?

(a) Auto key cipher

(b) Hill cipher

(c) Playfair cipher

(d) Additive cipher

The question was asked in my homework.

My question is taken from Cryptography topic in section Cryptography of Data Structures & Algorithms II

Answer 1

The correct choice is (d) Additive cipher

To explain: In poly alphabetic cipher each symbol of plain text is replaced by a different cipher text regardless of its occurrence. Out of the given options, only additive cipher is not a poly alphabetic cipher.