Do a numerical example of DES encryption using a one-round version of DES. Encrypt your Student ID with key FEDC BA98 7654 3210. When encrypting your student ID, left-pad it with zeroes. So, suppose your student ID is "01234567". Then the plaintext is "0000 0000 0123 4567". Write answers for parts a-i:
a. Derive K1, the first-round subkey.
b. Derive L0, R0.
c. Expand R0 to bet E[R0], where E[•] is the expansion function of Table 3.2.
d. Calculate A = E[R0] ? 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 € to get a 32-bit result, B.
g. Apply the permutation to get P(B).
h. Calculate R1 = P(B) ? L0.
i. Write down the ciphertext.