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 $K$ and the plaintext, namely:

a. Derive $K_1$, the first-round subkey.

b. Derive $L_0,R_0$.

c. Expand $R_0$ to get $E\left[R_0\right]$, where $E[\cdot ]$ is the expansion function of Table 3.2.

d. Calculate $A=E\left[R_0\right]\oplus K_1$.

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 $P\left(B\right)$.

h. Calculate $R_1=P\left(B\right)\oplus L_0$.

i. Write down the ciphertext.

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Hexadecimal notation: Binary notation: 0123456789 ABCDEF 0000 0001 0010 0011 0100 0101 0110 0111 1000 1001 1010 1011 1100 1101 1110 1111