A comparative study of symmetric key algorithm des, aes and blowfish for vide...
DES
1. Data Encryption Standard -
DES
DES was developed as a standard for communications and data
protection by an IBM research team, in response to a public
request for proposals by the NBS - the National Bureau of
Standards (which is now known as NIST).
By:
T.N.Srimanyu (12MCMB06)
Ritika Singla (12MCMB15)
M.Tech(IT)
2.
3. DES - Basics
DES uses the two basic techniques of cryptography -
confusion and diffusion.
At the simplest level, diffusion is achieved through
numerous permutations and confusion is achieved
through the XOR operation.
4.
5. DES - The 16 Rounds
The basic process in
enciphering a 64-bit data block
and a 56-bit key using the
DES consists of:
• An initial permutation (IP)
• 16 rounds of a complex key
dependent calculation f
• A final permutation, being the
inverse of IP
9. IMPROVED DES ALGORITHM
BASED ON IRRATIONAL
NUMBERS
IEEE Int. Conference Neural Networks & Signal
Processing
Zhenjiang, China, June 8~10, 2008
10. Irrational Numbers
Irrational numbers, which are similar to data
sequences generated form chaotic system, are infinite and
non-cyclic.
Therefore using irrational numbers to encrypt will provide
higher security without strict chaos synchronization.
11. Advantages
The improved scheme prevents the key from being
directly involved in the production of sub-keys.
It can increase the randomness of the production of the
sub-keys and use different sub-keys each group.
The key space is extended.
12.
13.
14. Conclusion
This paper designs an encryption algorithm with better
security, bigger secret-key space and higher encrypting
efficiency.
This scheme can expand the key space without any more
running time and enhance the security of the encryption
algorithm.
The algorithm has wider foreground applications based
on these advantages.
