Interactive end-of-chapter exercises


Learning Switches - Advanced

Consider the LAN below consisting of 10 computers connected by two self-learning Ethernet switches. (You may want to re-read section 6.4.3 in the text). At t=0 the switch table entries for both switches are empty. At t = 1, 2, 3, 4, 5, 6, 7, 8, and 9, a source sends to a destination as shown below, and the destination replies immediately (well before the next time step).



Question List


1. At t=9, what two nodes communicated? Write your answer in alphabetical order as x,y (If there is only enough information for 1 node, write that, and if there's no information, write 'n/a')

2. At t=8, what two nodes communicated? Write your answer in alphabetical order as x,y (If there is only enough information for 1 node, write that, and if there's no information, write 'n/a')

3. At t=7, what two nodes communicated? Write your answer in alphabetical order as x,y (If there is only enough information for 1 node, write that, and if there's no information, write 'n/a')

4. At t=1, what two nodes communicated? Write your answer in alphabetical order as x,y (If there is only enough information for 1 node, write that, and if there's no information, write 'n/a')




Solution


1. The transmission at t=9 was D-->H, so the answer is D,H.

2. The transmission at t=8 was D-->K, so the answer is K.

3. The transmission at t=7 was K-->G, so the answer is G.

4. The transmission at t=1 was K-->D, so the answer is n/a.



That's incorrect

That's correct

The answer was: D,H

Question 1 of 4

The answer was: K

Question 2 of 4

The answer was: G

Question 3 of 4

The answer was: n/a

Question 4 of 4

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