An existence bitmap has a bit for each record position, with the bit set to 1if the record exists, and 0 if there is no record at that position (for example,if the record were deleted). Show how to compute the existence bitmap from other bitmaps. Make sure that your technique works even in the presence of null values by using a bitmap for the value null.

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 0000000000000010000000000000001000000100000001000100000000000000 Suppose that the subkey for the current round is this 48 bit number: 000000000000000001000000000000000000000000000000 What does the 64 bit state look like after the IP transformation is applied to the input? 00000000000110000100000000000000 Now find Lo and Ro, the left and right halves of the state. Lo 01000000010000000000000000010000 = Ro=00000000000000100000000000000000 What is the result of applying the expansion box to R₁? E(Ro) = 00000000000000100000000000000000 What is the result of XORing the subkey with E(Ro)? k₁ E(Ro) = 00000000000000100000000000000000 We now apply the S-box transformation. S(k₁ E(Ro)) = 11011000110110001101111110111100 Finally we apply the permutation box to complete the function f. f(Ro) = P(S(k₁ + E(Ro)))…

If the sequence number space is k-bit, use Go-Back-N and selective-repeat. How big may the sender window be?

What are the various problems that could arise in Non-Return to Zero (NRZ) encoding if a continuous stream of 0s or 1s is sent?  Instead of writing an essay, try writing in bulleted form, briefly explaining what you understand from the findings.