Encryption algorithm based on Lagrange interpolation

Abstract

This paper attempts to improve the classical encryption algorithm by using Lagrange interpolation method. A large positive integer is used to represent plaintext, that is, we can use plaintext as a positive integer to carry out Lagrange calculation. Because ciphertext is a big positive integer, not repeatable, it is impossible to analyze ciphertext by probability. The algorithm increases the key space and the difficulty of brute force cracking. This algorithm has the security of one-time pad. The length of the key can be less than the length of the plaintext, and the choice of the key is more flexible.