Level 1 Domain Partitions

What happens if a level 1 routing domain is partitioned through a failed link? The problems that occur in a level 1 partition are similar to the problems encountered with a level 2 partition; let's look at Figure 3-8 and work through a partition to find out why.

Figure 3-8. Level 1 routing domain partitioning

Once the link between A and B breaks, the 49.1111 level 1 routing domain appears to be two level 1 routing domains with the same domain number. A and B will now both advertise that the 49.1111 domain is reachable through them, which causes some of the end systems attached to them to be unreachable, as the other level ...

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