private-key cryptography definition 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 sender and the recipient of the message must agree on a common key via some alternative secure channel. Public-key cryptography
gives an answer to this problem.