Scalable Implementation of Array of 8-bit-Based RSA With Large Key Size

Since 1977, many cryptographic attacks have been applied to RSA (Rivest Shamir Adleman). Researchers have proposed security solutions against these attacks, such as padding into the data to be encrypted and using keys of significant length from 1024 bits to 4096 bits. Therefore, to implement RSA., we need an arithmetic unit working with a big integer like in Python and Maple. The maximal length of almost programming platforms doesn't exceed 64 bits. This article presents a scalable algorithm of the RSA cryptosystem with a large key size based on arrays of 8 bits. Therefore, keys, message to be encrypted, and encrypted data are arrays. Each array case is of type unsigned integer 8 bit. However, it codes only 7 bits; the 8th bit is used for the carrying of an arithmetic operation. The proposed arithmetic unit allows subtraction, division, and multiplication of large numbers, and it is scalable with all platforms like C/C++, Java, and PHP. The proposed algorithm is implemented on MATLAB environment. Simulation tests are verified with Python, where we find that the proposed implementation generates RSA keys, encrypts, and decrypts data with 0% failure.