Backbround:
Developed by Professor Edward Schaefer of Santa Clara University. An educational rather than a secure encryption algorithm. Has similar properties and structure to DES with much smaller parameters. Backbround
XOR Operation:
XOR Operation 0 1 0 0 1 1 1 0 1 0 1 0 ⊕ 0 0 0 0 -------------- 1 0 1 0 1 0 1 0 ⊕ 1 1 1 1 -------------- 0 1 0 1 Truth Table Example (1) Example (2)
Structure:
Structure
S-DES Scheme (2):
S-DES Scheme (2)
Key Generation:
Key Generation LS-1 2 3 4 5 1 LS-1 7 8 9 10 6 LS-2 3 4 5 1 2 LS-2 8 9 10 6 7
Initial and Final Permutation:
Initial and Final Permutation
Function fk:
Function f k
Function F:
Function F XOR with SK1
S-BOXES:
S-BOXES S1 = Intersection of row & col Row = (1 4)b Col = (2 3)b S0 = Intersection of row & col Row = (1 4)b Col = (2 3)b Eg . 1010 row = 10 col = 01
SW Function:
SW Function SW 5 6 7 8 1 2 3 4