Specifications

CHAPTER 3
Spanning Tree
Spanning Tree Protocol (STP) works by selecting a root bridge and then selecting one loop-free path from the root bridge
to every other switch. (STP uses the term bridge because it was written before there were switches.) Consider the follow-
ing switched network (see Figure 3-1).
Spanning Tree must select
n One root bridge
n One root port per nonroot bridge
n One designated port per network segment
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CCNP SWITCH 642-813 Quick Reference by Denise Donohue
FIGURE 3-1
Example Switched
To p o l o g y
A
000c.1111.0011
B
000c.2678.1010
C
000c.321a.bcde
000c.8181.1122
E
000c.2679.2222
100
Mbps
1000
Mbps
10
Mbps
10
Mbps
100
Mbps
100
Mbps
100
Mbps
0/1
0/2
D
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