2) (24 pts) Answer the following short answer questions a) (2 pts) Suppose that setting up a call requires reserving N link segments (or through N-1 switches). Each segment is available with probability p. What is the probability that a call request can be completed? b) (2 pts) A 1Mbyte file is to be transmitted over a 1Mbps communication line that has a bit error rate p=10-6, what is the probability that the entire file is transmitted without errors? MPps VTs d) (4 pts) Explain why HDLC protocol applies bit stuffing. (Note that HDLC uses 01111110 as the frame marker.) And please mark the stuffed bits in the following bit sequence e (2 pts) Suppose a frequency spectrum of bandwidth bandwidth. What is the bit rate per channel? Assume all channels have the same S WHz is divided into M channels of equal Im "Al ate g) (2 pts) Explain why CSMA/CD cannot be used in wireless environment? Or in other words why it is difficult for a wireless node to detect a collision? no de is harn -1 (2 pts) Suppose a sliding window algorithm is implemented using a SWS-4 and a RWS 3, will 6 sequence numbers (i.e. 0.1,2,3,4)be sufficient to correctly distinguish all packets that are received? Explain your answer. for example, an old sequence number of O is not mistaken for a new sequence number of 0)