Consider the network below with each link length equal to one. Distance vector routing is used. Initially each node knows the correct next hop and path length for its shortest path to node 4. Then suppose the link between nodes 3 and 4 fails. a. Following the failure, suppose that nodes 1, 2, 3 update the component of their distance vector for destination 4 synchronously. For each of the nodes 1, 2, 3, show the sequence of (next hop, path length) values for the iterations of the distance vector algorithm. Note that by synchronous update, we mean that all the nodes exchange their distance vectors with their neighbors simultaneously and then update their distance vectors simultaneously. b. Repeat part (a) but assume that the distance vector algorithm uses split horizon.

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