Its security is based on the difficulty of dividing big prime number. The private key and public key are the function of a pair of big prime number(decimal number between100and200bit or larg-er).

• 其公开密钥和私人密钥是一对大素数(100到200个十进制数或更大)的函数。 从一个公开密钥和密文中恢复出明文的难度等价于分解两个大素数之积。