Difference between 3DES and AES Can any one tell me the difference between 3DES / AES ?? And if we use 3DES there will be any decrease in performance?
AES, otherwise known as Rijndael and FIPS-197 is a symmetric block cipher that can accept variable block length and key length. The specification for AES can use keys with a length of 128, 192, or 256 bits to encrypt blocks with al length of 128, 192 or 256 bits (all nine combinations of key length and block length are possible). Both block length and key length can be extended very easily to multiples of 32 bits. AES can be implemented very efficiently on a wide range of processors in software, or directly in hardware.
3DES, Triple DES, or Triple Data Encryption Standard, is based on the DES algorithm developed by an IBM team in 1974 and was adopted as a US standard in 1977. 3DES uses three 64-bit long keys (overall key length is 192 bits, although actual key length is 56 bits). Data is encrypted with the first key, decrypted with the second key, and finally encrypted again with the third key. Note that many implementations (including Check Point's) use the same key for the "first" and "third" key, thus yielding a key strength of 112 bits, not 168 bits.
Answer DES was originally designed to run in specialized hardware and is considered "computationally expensive" on general-purpose processors. AES was designed to run efficiently on a variety of processors, including general-purpose ones. Given the same hardware without specific encryption acceleration, AES should give you better performance (and more security to boot)--test reports I've seen on various Nokia platforms bear that out. However, the various cryptographic accelerators supported by Check Point (as of this writing at least) will yield better performance with 3DES than with AES.
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RobertGraham - 06 Jan 2004
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Difference between 3DES and AES 
2005-08-12 
Difference between 3DES and AES 
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