L24 - Distance vector routing Related to the Bellman-Ford...

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Distance vector routing Related to the Bellman-Ford Algorithm. Let node 1 be the destination node. Find the shortest path from every node to node 1. i Define D as the cost (called “distance”) of the shortest h 1 path from i to 1 that uses at most h links. D = 0 for any h h. i Initially: D = 4 . 0 Iteratively, we find ii j j D = min [d + D ] for all i ± 1 h+1 h j and the new associated path from node i for h+1 is , for the minimizing j, the prior path from j to 1 in h steps augmented by the link from i to j.
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A router needs to know the direct cost to each of its attached neighbors. Also, each router maintains a table of its best known distance to each destination and the link to go to next. The estimated distance from the node j to jk destination k is D , and these numbers are reported to its neighbors for the next Bellman- Ford-like computation.
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Node i directory Destination Est. Cost next node -- - - - An individual node does not need to know about the other parts of a route.
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Cost is a tricky assignment in routing decisions.
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L24 - Distance vector routing Related to the Bellman-Ford...

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