Securing text using Rabin-p public key cryptosystem and Spritz algorithm in a hybrid cryptosystem: a tutorial

Abstract

Abstract Security in the process of sending digital messages is very important to avoid being theft by unwanted parties. In order to protect the messages, modern cryptography techniques come into play. Public key cryptosystem based on the integer factorization such as Rabin-p could provide high confidentiality as long as the modulus is of a very large integer. On the contrary, having a longer modulus causes two problems: the longer the size of the ciphertext and the longer the time needed for the decryption process. In order to solve this problem, in this research, we combine Rabin-p cryptosystem and Spritz algorithm in a hybrid cryptosystem. Message is encrypted with Spritz algorithm, and the key of Spritz algorithm is then protected by Rabin-p cryptosystem. In this scheme, the encrypted message can be recovered back to the original message while maintaining small decryption time.