In this problem we will work through a round of DES. For notational simplicity, assume it is the first round. Please enter all answers as strings of 0's and 1's. The input is the 64 bit block 0100000000000000000001000000000000000000000100000000000000000000

Suppose that the subkey for the current round is this 48 bit number: 000000000000000000000000000000000000000000001000

a) What does the 64 bit state look like after the IP transformation is applied to the input?

b)Now find L0 and R0 , the left and right halves of the state. L0= ? R0=?

c)What is the result of applying the expansion box to R0 ? E(R0)=

d)What is the result of XORing the subkey with E(R0) ? k0E(R0)=

d)We now apply the S-box transformation. S(k0E(R0))=

e)Finally we apply the permutation box to complete the function f . f(R0)=P(S(k0E(R0)))=

f) We can now compute the state of DES going into the next round. L1= ? R1= ?