Decryption speed up of RSA by pre-calculation
Kyuchol Kim, Yong Bok Jong, Yunmi Song · 2023
It is easy to increase the encryption speed by using small public exponent in RSA. In this case, private exponent is full sized (on the order of modulus) and so, most of calculation costs are allocated to decryption. Meanwhile, it is not easy to speed up decryption by reducing private parameters for the security problem. From this, many researches have been done to increase the decryption speed without compromising the security. This paper presents two new modified schemes for implementing the RSA public-key cryptosystem, with the goal of reducing or controlling the time for encryption and decryption, while attempting to maintain security. In other words, we proposed two variants of RSA designed to speed up decryption. Our first variant allows the cost of encryption and decryption to be balanced without modifying the prime generation. Second variant has the faster decryption than the other RSA variants (e.g., rebalanced RSA) with two balanced primes.