Interactive end-of-chapter exercises


Dijkstra's Link State Algorithm - Advanced

Consider the incomplete 6-node network shown below, with the given link costs.

Consider the completed table below, which calculates the shortest distance to all nodes from Z:
================================================
|    Node     |    Shortest distance from Z    |    Previous Node   |
================================================
       Z                                0                                     n/a   
       W                               5                                     Z   
       Y                                7                                     Z   
       X                                13                                   W   
       U                                14                                   W   
       V                                14                                   W   
================================================



Question List


1. For link X, what is the cost associated with this link? If the answer can't be determined given the information, respond with 'n/a'

2. For link Y, what is the cost associated with this link? If the answer can't be determined given the information, respond with 'n/a'




Solution


1. The prior node in the path to X is W, and we know the shortest distance of both X (13) and W (5), so 13 - 5 = 8 which is X.

2. Because the link is never used, we cannot determine the value of Y, so the answer is n/a.



That's incorrect

That's correct

The answer was: 8

Question 1 of 2

The answer was: n/a

Question 2 of 2

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