大数运算在网络安全中的应用

大数运算在网络安全中的应用以RSA算法为例.设明文为p,加密算法为E,解密算法为D,在一定条件下,找到两素数p和q,经转换得到n、d、e,再经计算得加密消息c,完成对加密信息的解密.d和e可互换.在非对称加密中,n、d构成公钥,n、e构成私钥,e则自己保留.发送信息使用e加密,接收信息时使用d加密,即只有拥有e能对其解密.RSA安全性在于对于大数n,无有效方法将其分解,从而保证加密信息的安全.

Application of Large-Number Operation in Network Safety

The application of large-number operation in network safety takes the RSA algorithm for example. If the plaintext is P, encryption algorithm is E, decryption algorithm is D, find two prime numbers in certain condition, which can be transformed as n, d, and e. Then it can complete decrypting cipher text and getting cipher text through calculation. D and e can be exchanged. The public key is made up of n and d, private key is made up of n and e in the unsymmetrical system, e is kept by oneself. It can be encrypted with e and d when sending and receiving message. But only e can be used as decrypting. The safety of RSA depends on the large-number n, because there is no effective way to decompose it. So it can assure the safety of cipher text.