Q3. MAC Protocols(25 pts) List one advantage and one disadvantage of using channel-partitioning MAC protocols. (6 pts) a. b. Describe the Ethernet CSMA/CD with exponential backoff algorithm. (7 pts) c. Consider the following old fashion bus-based linear Ethernet network that is 2km long. Assume that propagation speed of electromagnetic waves sent over the medium is 2*108 m/s and the transmission rate of the network is 10Mbps. What is the minimum frame size (in bits) necessary to ensure that CSMA/CD will work properly for this network? Explain your reasoning. (12 pts) Q4. Routing Algorithms(25 pts) Consider the network of five routers below, with edge weights labeled. R1 R2 RS R4 R3 a. Show the step-by-step operation of Dijkstra's algorithm for R3. (15 pts) b. Name two problems that would arise if all routing in the Internet was done using Link State and Dijkstra's algorithm. Does Distance-Vector routing suffer from these? (5 pts) What are the differences between routing and forwarding? Briefly explain each of them. (5 pts) c