Performance Improvement Technique of RSA Algorithm in Document Data Security

One of the first public key schemes was developed in 1977 by Ron Rivest, Adi Shamir, and Len Adleman at MIT and first published in 1978. Since then, the RSA scheme has become the most widely accepted and applied public-key encryption approach. RSA is a block cipher where the plaintext and ciphertext are integers between 0 and n - 1 for some $n$. However, since the calculations involved (both in key generation and in encryption/decryption) are complex, the larger the key size, the slower the system will run. To overcome the performance constraints of the RSA algorithm, various techniques such as iteration, Divide and Conquer, and Square and Multiply have been developed. Tests were conducted on files with various key lengths to evaluate encryption and decryption performance. The results show that all three algorithms experience an increase in computation time as the key length increases. The iteration algorithm shows the best performance for short keys, while the square and multiply algorithm provides the highest efficiency for medium to long keys. Further testing recommends using square and multiply for keys of 128 bits and above due to its superior efficiency. It can be concluded that the selection of appropriate support algorithms can overcome RSA's performance issues without compromising security, as well as provide suggestions for further security analysis and development of more efficient algorithms.