In designing a network topology, be sure your topology does not contain any loops. A loop exists when there is more than one path between any two end nodes in your network. A loop can result in what is referred to as broadcast storms, where Ethernet frames become caught in repeating cycles that needlessly consume network bandwidth. This often results in poor network performance. An example of an invalid loop topology is shown in Figure 7.
1 | 2 | 3 | 4 | TX | 5 | RX | DC In |
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Ethernet Hub
Figure 7 Invalid Loop Topology
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