Question

1.0. Suppose the network is as follows, where distance-vector routing update is used. Each link has cost 1, and each router has entries in its forwarding table only for its immediate neighbors (so A’s table contains 〈B,B,1〉, 〈D,D,1〉 and B’s table contains 〈A,A,1〉, 〈C,C,1〉).

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(a). Suppose each node creates a report from its initial configuration and sends that to each of its neighbors. What will each node’s forwarding table be after this set of exchanges? The exchanges, in other words, are all conducted simultaneously; each node first sends out its own report and then processes the reports arriving from its two neighbors.

(b). What will each node’s table be after the simultaneous-and-parallel exchange process of part (a) is repeated a second time?

Hint: you do not have to go through each exchange in detail; the only information added by an exchange is additional reachability information.

Answer 1

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