# Symmetric Encryption ``` DES/3DES AES Twofish Blowfish Serpent IDEA RC4, RC5, RC6 CAST ``` Key Length for symmetric is 56-256 bits


DES	Data Encryption Standard 56 bit key encryption (16 cycles of 48 bit subkeys)
3DES	Triple DES 168 bit key encryption (48 cycles)
AES	Advanced Encryption Standard A block of cipher uses a 128 bit block size and a 128-, 129, or 256 bit key size.

DES

Data Encryption Standard

56 bit key encryption (16 cycles of 48 bit subkeys)

3DES

Triple DES
168 bit key encryption (48 cycles)

AES

Advanced Encryption Standard
A block of cipher uses a 128 bit block size and a 128-, 129, or 256 bit key size.

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