1. How many step function do Round 1 and 2 each have in S-AES?

a) 4 and 3

b) Both 4

c) 1 and 4

d) 3 and 4

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2. For a key 25D5 and PT input A479 what is the output we obtain after the “add round key” function?

a) F34D

b) 81AC

c) 79DF

d) 327D

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3. The output of the previous question, on passing through “nibble substitution” gets us the output

a) 3267

b) 1344

c) 64C0

d) CA37

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4. The output of the previous question on passing through the “shift row” step function gives us the output

a) C046

b) 0C64

c) 64C0

d) 640C

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5. The output of the previous question on passing through the “mix columns” step function gives us the output

a) 3252

b) 3743

c) 3425

d) 3473

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6. On performing the mix column transformation on the matrix

(Verify for the first column only)

a) True

b) False

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7. The inverse transformation matrix times the forward transformation matrix equals the identity matrix.

a) True

b) False

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8. Which of the following are true

i) In the AES key expansion algorithm, the function g() operates on w i+3

ii) Perform a one-byte right circular rotation on the argument 4-byte word

iii) The round constant follows the formula RC[j] = RC[j − 1]

a) i) ii)

b) ii) only

c) i) only

d) All

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9. How many round keys are generated in the AES algorithm?

a) 11

b) 10

c) 8

d) 12

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10. Which function can be used in AES multiplication

a) m(x)=x^{7}+x^{4}+x^{3}

b) m(x)=x^{8}+x^{4}+x^{3}+x+1

c) m(x)=x^{8}+x^{3}+x^{2}+x+1

d) m(x)=x^{8}+x^{5}+x^{3}+x

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^{8}+x

^{4}+x

^{3}+x+1 stands for 100011011 which is an irreducible polynomial. Others are not irreducible polynomials.