Question 5: Link State and Distance Vector Routing [20 marks] Consider the network shown in the figure below a) [8 marks] Show the operation of Dijkstra's (Link State) algorithm for computing the least cost path from B to all destinations. b) [ 3 marks] From these results, show the least cost path from B to D, and briefly describe (in a sentence) how you got that answer from your work in part a). c) [5 marks] Consider now the ring network shown below. What are distance vectors in nodes B, and C ? d) [4 marks] Now suppose that the only destination in this new network in the figure above is A (i.e., we will only consider routing table entries here for A). Suppose that link from A to B fails (its cost goes to infinity) Once the failure is detected, approximately how many messages will be exchanged by all nodes by the distance vector algorithm until no more messages are exchanged? Justify your answer in one or two sentences. Note: you do not have to run the distance vector algorithm (it would take you hours); also, your answer need not be exactly correct, it can be off by a bit. This question is trying to get at the essence of the count-to-infinity problem )