BPDU Entering MST Region
Jul 08,2008 00:00 by admin
BPDU Entering MST Region

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The objective of having an IST is to make the MST region appear as a single bridge. This is an important distinction because it allows for MST to have large Layer 2 networks. For instance, Region 10 is seen by other regions as one bridge with one port participating in spanning tree. The IST master bridge is used as transit by the local bridges within the region.

It is important to understand that one CST is available for the entire Layer 2 network. The CST topology is built based on IST. Also, remember that within the region, another spanning tree is locally significant to the region, as discussed in the next section.