<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.
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Nearby terms: Private Automatic Branch eXchange « Private Branch Exchange « private key « private-key cryptography » Private Manual Branch eXchange » privileged instruction » PRL