Accelerating RSA Encryption Using Random Precalculations

RSA encryption and digital signature algorithm is considered secure if keys are 1024-4096 bits long. Since it requires modular exponentiation on numbers of this length, embedded systems need either a cryptographic co-processor or a fast CPU to calculate ciphertexts and signatures. In many applications, the sender is resource-scare, so optimization is necessary. In our paper we show a method for precalculations that accelerates the real-time performance of the sender in the expense of additional calculations at the receiver. When completed, the receiver gets an RSA-equivalent ciphertext for the encryption algorithm.