m |
|||
| Line 20: | Line 20: | ||
---- | ---- | ||
| + | ''' | ||
| + | == Accompanying Lecture Notes == | ||
| + | ''' | ||
| + | ---- | ||
| + | |||
| + | '''Data Encryption Standard(Block Cipher)''' | ||
| + | |||
| + | * '''Introduction''' | ||
| + | |||
| + | DES works on blocks of bits or binary numbers--the 0s and the 1s common to digital world. It encrypts group of 64 plaintext bits(one block) and returns 64 ciphertext bits. To do the encryption, DES uses keys which are also 64 bits long. However, every 8th key bit is ignored in the DES algorithm, so that the effective key size is 56 bits. | ||
| + | |||
| + | * '''Block Cipher Primitives''' | ||
| + | |||
| + | Confusion : An encryption operation where the relationship between plaintext and ciphertext is obscured. Today, a common element for achieving confusion is substitution, which is found in both AES and DES. | ||
| + | |||
| + | Diffusion : An encryption operation where the influence of one plaintext symbol is spread over many ciphertext symbols with the goal of hiding statistical properties of the plaintext. A simple diffusion element is the bit permutation, which is frequently used within DES. | ||
| + | |||
---- | ---- | ||
==[[2015_Summer_Paar_Data Encryption Standard(DES)_Divya Agarwal and Katie March_comments | Questions and comments]]== | ==[[2015_Summer_Paar_Data Encryption Standard(DES)_Divya Agarwal and Katie March_comments | Questions and comments]]== | ||
Revision as of 08:41, 10 June 2015
Data Encryption Standard(DES)
A slecture on Cryptography by student Divya Agarwal and Katie Marsh
Partly based on the Summer 2015 lecture material of Prof. Paar.
Link to video on youtube
Accompanying Lecture Notes
Data Encryption Standard(Block Cipher)
- Introduction
DES works on blocks of bits or binary numbers--the 0s and the 1s common to digital world. It encrypts group of 64 plaintext bits(one block) and returns 64 ciphertext bits. To do the encryption, DES uses keys which are also 64 bits long. However, every 8th key bit is ignored in the DES algorithm, so that the effective key size is 56 bits.
- Block Cipher Primitives
Confusion : An encryption operation where the relationship between plaintext and ciphertext is obscured. Today, a common element for achieving confusion is substitution, which is found in both AES and DES.
Diffusion : An encryption operation where the influence of one plaintext symbol is spread over many ciphertext symbols with the goal of hiding statistical properties of the plaintext. A simple diffusion element is the bit permutation, which is frequently used within DES.
Questions and comments
If you have any questions, comments, etc. please post them here.
