The standard DES algorithm has 16 rounds to come up with an encrypted message. In this...

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The standard DES algorithm has 16 rounds to come up with an encrypted message. In this lab, we just suppose the DES has only one round with the round 48-bit key EOBE6E662267 (note here the key is 48 bits long instead of 64 bits because we actually skip the step of key generation and just assume we already got the round key). Given the cipher text 266E2A7732713036, what is its plaintext using the key EOBE6E662267 with one round? The standard DES encryption procedure is briefly summarized in figure 1 below and one of the most significant features for standard DES algorithm is that both encryption and decryption follow the same procedure. The only different is the key in decryption is from K16 to K1 from round 1 to: round 16. 32 bits LI-1 Mixer Swapper r(RJ-11) LI 32 bits 32 bits R1-1 Each round RI 32 bits 64-bit plaintext Initial permutation Round 11 Round 2 : Round 16 Final permutation 64-bit ciphertext K 48-bit K 48-bit K16 48-bit IP 585042 34 26 18102 60 5244 36 28 20 124 62 5446 3830 22 146 64 564840 32 24 168 574941 33 25 17 91 595143352719113 61 53 45 37 29 21 135 63 55473931 23 157 DES Round-key generator 56-bit cipher key What to be submitted and included in the lab report for this question: The following steps are illustrated in more details to come up with the plaintext, Step 1: Show the result after the original 64-bit plaintext is re-ordered by the table IP (initial permutation), in which IP is illustrated below: The standard DES algorithm has 16 rounds to come up with an encrypted message. In this lab, we just suppose the DES has only one round with the round 48-bit key EOBE6E662267 (note here the key is 48 bits long instead of 64 bits because we actually skip the step of key generation and just assume we already got the round key). Given the cipher text 266E2A7732713036, what is its plaintext using the key EOBE6E662267 with one round? The standard DES encryption procedure is briefly summarized in figure 1 below and one of the most significant features for standard DES algorithm is that both encryption and decryption follow the same procedure. The only different is the key in decryption is from K16 to K1 from round 1 to: round 16. 32 bits LI-1 Mixer Swapper r(RJ-11) LI 32 bits 32 bits R1-1 Each round RI 32 bits 64-bit plaintext Initial permutation Round 11 Round 2 : Round 16 Final permutation 64-bit ciphertext K 48-bit K 48-bit K16 48-bit IP 585042 34 26 18102 60 5244 36 28 20 124 62 5446 3830 22 146 64 564840 32 24 168 574941 33 25 17 91 595143352719113 61 53 45 37 29 21 135 63 55473931 23 157 DES Round-key generator 56-bit cipher key What to be submitted and included in the lab report for this question: The following steps are illustrated in more details to come up with the plaintext, Step 1: Show the result after the original 64-bit plaintext is re-ordered by the table IP (initial permutation), in which IP is illustrated below:

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Solutions Step 1 To decrypt the given ciphertext with the provided DES key in a single round you can ... View the full answer