Actions That Result From Cbpdu Information - 3Com 4007 Implementation Manual

The bridges that are chosen as the best path, called designated bridges,
form the second level of the hierarchy.
A designated bridge relays network transmissions to the root bridge
through its root port. Any port that transmits to the root bridge is a
root port.
The designated bridges also have designated ports — the ports that
are attached to the LANs from which the bridge is receiving
information.
Figure 3 shows the hierarchy of the STP bridges and their ports.
Figure 3 Hierarchy of the Root Bridge and the Designated Bridge
To designated port
To root port
To root port

Actions That Result from CBPDU Information

From the information that the CBPDUs provide:
Bridges elect a single bridge to be the root bridge. The root bridge has
the lowest bridge ID among all the bridges on the extended network.
Bridges calculate the best path between themselves and the root
bridge.
Root bridge
Designated bridge
STP Terms and Concepts
To designated port
Bridge
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