资料来源 : Free On-Line Dictionary of Computing

private-key cryptography
     
         As opposed to {public-key cryptography}, a
        cryptographic method in which the same key is used to encrypt
        and decrypt the message. Private-key algorithms include the
        obsolescent {Data Encryption Standard} (DES), triple-DES
        (3DES), the {Advanced Encryption Standard} (AES), also known
        as Rijndael, Blowfish, Twofish RC2, {RC4}, RC5 and RC6.
     
        A problem with private-key cryptography is that the emitter
        and the recipient of the message must agree secretly on a
        common key beforehands; but how can they do so?
     
        {Public-key cryptography} gives an answer to this problem.
     
        (2003-04-12)