Sequential and Parallel Cascaded Convolutional Encryption with Local Propagation: Toward Future Directions in Symmetric Cryptography

Worldwide symmetric encryption standards such as DES (data encryption standard), AES (advanced encryption standard), and EES (escrowed encryption standard), have been - and some of them still are - extensively used to solve the problem of communication over an insecure channel, but with today´s advanced technologies, they seem to not be as secure and fast as one would like. In this paper, we propose efficient alternatives based on special classes of globally invertible cascaded convolutional transducers. The proposed symmetric encryption techniques have at least four advantages over traditional schemes based on Feistel ciphers. First, the secret key of a cascaded convolutional cryptosystem is usually much easier to generate. Second, the encryption and decryption procedures are much simpler, and consequentially, much faster. Third, the desired security level can be obtained by just setting appropriate values for the parameters of the convolutional cryptosystem. Finally, they are much more parallelizable than symmetric encryption standards based on Feistel ciphers