Modular exponentiation with a large modulus, which is usually accomplished by repeated modular multiplications, has been widely used in public key cryptosystems for secured data communications.

• 中文摘要模指数运算通常是由一连串的模乘法所组成，而在公开金钥密码系统中，为了安全的考量，我们常会选用非常大的模数。