Consider the individual acknowledgment protocol. Assume that during an execution, the system reaches a state where LAR = 9, and LFS = 3. Which of the following statements concerning the value of NFE at this state may be true, which of them is/are definitely false, and which of them is/are inconclusive. Briefly explain why.
a)Is it possible to have a state in the sliding window protocol, such that LAR = 9, NFE= 13, LFS = 3? Briefly explain why it is or it is not possible.
b)Is it possible to have a state in the sliding window protocol, such that LAR = 10, NFE= 12, LFS = 3? Briefly explain why it is or it is not possible.
c)Is it possible to have a state in the sliding window protocol, such that LAR = 10, NFE=11, LFS = 4? Briefly explain why it is or it is not possible.