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Question 1. This problem provides a numerical example of encryption using a one-round version of DES. We start with the same bit pattern for the key and the plaintext, namely: Hexadecimal notation: Binary notation: ABCDEF0123456789 1010 1011 1100 1101 1110 1111 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 a. Derive the first-round subkey K1 b. Derive Lo and Ro. c. Expand Ro to get E[Ro], where EL] is the expansion function of Table 3.2 d. Calculate A=E[Ro]?K1' e. Group the 48-bit result of (d) into sets of 6 bits and evaluate the corresponding S-box substitutions. f. Concatenate the results of (e) to get a 32-bit result, B. g Apply the permutation to get P(B). h. Calculate R1P(B) Lo i. Write down the ciphertext