Last time i had many mistakes this time the problem is on in the cardif but i dont get it i do the math and the resuls are right.

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1 Answer 1


If you compare the two tables, the subnet masks don't match for Cardiff F0/0. The subnet mask on the second table is too small (host subnet too large), and it overlaps the next subnet.

PC5 has an invalid host IP address. The last valid host address must be an even number. The IP address assigned to PC5 is the broadcast address for the subnet.

Let me give you the benefit of my experience. You probably should have used a single table. In my experience, duplicate information will always get out of sync. That appears to have been the problem here. The subnet mask in the first table appears to be correct, but it does not match the subnet mask in the second table. Had you just made another column in the first table for the interface IP address, you probably would not have made the overlap mistake.


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