Question 2 (I) When a medium access control protocol should control access to a medium? (II) TDMA is a channel partitioning protocol. If the channel capacity is R bps, what is the available data rate to each user when N users exist? (III) Assume there are N users connected to a wireless access point. Each user produces an almost constant traffic rate R. The channel capacity is N R. Which one of the following MAC protocols is more suitable for this system, TDMA or CSMA? explain your answer. (IV) CSMA/CD is implemented in the link-layer of Ethernet. What is CSMA and what is CD? (V) In CSMA/CD, after the 5th collision, what is the probability that a node chooses K = 10? The result K = 10 corresponds to a delay of how many seconds on a 100 Mbps Ethernet? Note: For Ethernet, the actual amount of time a node waits is K x 512 bit times, i.e., K times the amount of time needed to send 512 bits