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| The process of S-DES happens in two rounds as you can see in attachment:s-des-map.pdf. | The plaintext is processed by S-DES in two rounds where each round encrypts half of the plain text after it has been permuted. The key for each round is generated by a seperate process and both can be seen in attachment:s-des-map.pdf. S-DES operates on 8-bit blocks and uses a 10-bit key. DES uses 64-bit blocks and a 56-bit key. == Block Cipher Principles == Block ciphers use a fixed length block of plaintext and produce an equal sized block of cipher text. |
Block Ciphers and DES
S-DES
The plaintext is processed by S-DES in two rounds where each round encrypts half of the plain text after it has been permuted. The key for each round is generated by a seperate process and both can be seen in attachment:s-des-map.pdf.
S-DES operates on 8-bit blocks and uses a 10-bit key. DES uses 64-bit blocks and a 56-bit key.
Block Cipher Principles
Block ciphers use a fixed length block of plaintext and produce an equal sized block of cipher text.