用RSA实现电子商务系统中的数字签名

安全性、易用性与加解密的效率是建构PKI客户端系统的重要内容。这些问题与密钥的管理、加密的硬件实现有关。RSA的安全基于大数分解的难度，其公开密钥和私人密钥是一对大素数的函数，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。鉴于这种特性，利用RSA公钥密码体制可在电子商务中实现数据的加密和数字签名。文中介绍了RSA体制的算法过程及RSA体制在加密和数字签名中的应用，分析了RSA实现的效率和安全性。

Use RSA to Implement the Digital Signature under Electronic Commerce System

Security,ease of use and efficiency of encryption ＆decryption are the important topics when constructing a PKI client system. These problems are related to the key management and the hardware realization of encryption.At the same time,Security of R.SA is based on the difficulty in resolving a large number.The public key and the secret key are functions of a pair of large prime numbers.The difficulty in converting the cipher text into the plaintext through the public key equals to that of resolving the product of two large prime numbers. According to this characteristic, data encrypting and digital signature can be realized in electronic commerce with the help of R.SA public key cryptosystem. The arithmetic process of RSA system was introduced, followed by introducing the apphcation of R.SA system in encryption and digital signature, and analyzed the efficiency and security in realizing the RSA system.