Classical Cryptosystem | Substitution Cipher | Permutation Cipher | Shift (Caesar) Cipher

Classical cryptosystem is the symmetric or single-key cryptography which uses single key of encryption and decryption. Substitution cipher replaces the plaintext letter by another letter while converting to the cipher text. In contrast, permutation cipher simply reorders the alphabets in plaintext without changing them. For more details, visit http://genuinenotes.com