Method for encrypting plain text

Abstract

Plain text that is part of the plain text message is encrypted using a reversible decomposition function, which allocates two plain text parts to each plain text to be encrypted. These plain text parts are then encrypted with at least one encryption function in two separate steps. Since the decomposition function is reversible, the inverse function can always be used to unambiguously derive the original plain text from the plain text parts. This is now used to decrypt the cipher text message created by the encryption with the cipher text parts using a suitable decryption. The cipher text parts are decrypted one after the other using at least one decryption function to then recover the plain text. A conventional initialization vector for encryption and decryption is then replaced by selected or all bits of the second plain text part or a bit sequence derived from this.