Date post: | 14-Jan-2017 |
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Advanced Encryption Standard-Ignatius Gonsalves
1. What is AES?2. What is DES?3. Why AES is better than DES?4. Behind the scenes5. Present use of AES
What Is AES?
• Also known as Rijndael•Developed by Joan Daemen and Vincent Rijmen• A Successor of Data Encryption Standard (DES)
What is DES?Data Encryption Standard
Bit length = 56 bitsDesigned 35 years agoPurpose - Secure government communications
A series of challenges were sponsored……
Challenge 1• 1997• 84 days• “ The secret
message is: Many hands make light work”
Challenge 2• 1998• 3 Days• “Time for
those 128-256 bit keys”
Challenge 3• 1999• 22 hrs 15 mins• “See you in
Rome !”
Deep Crack Computer
AES vs DES
DES AESDevelopedKey LengthCipher TypeBlock SizeSecurity
1977 200056 bits 128,192 & 256 bits
Symmetric Block Cipher64 bits 128 bitsInadequate Secure
Behind the scenes
AES
Private Data Ex: Credit card no.
Secret Key
Ciphered Text
AES
Ciphered Text
Secret Key
Private Data
Lets have an in-depth info……..
Byte Substitution
Shift Rows
Mix Columns
Add Round Keys
Encryption
Byte Substitutio
n
• Data is converted into a matrix
Shift Rows• Rows are
shifted to left
Mix Column
Add Round Key
Columns are transformedBy a special
function
Bytes of matrix are x-or’ed to key
Present use Archive and
compression tools
File Encryption
Disk Partitions
Thank You