The Spanning Tree Protocol Window 3-23Using the TSX-1620 Bridge View
In a network designed with multiple bridges placed in parallel (i.e., attached to
the same network segment), Spanning Tree selects a controlling Root Bridge and
Port for the entire bridged local area network, and a Designated Bridge and Port
for each individual network segment. The Root bridge is the one that selects one
of two or more available bridge paths between two end stations, basing its
decision on factors associated with each of the bridges in the path. A Designated
Port/Bridge for a network segment relays frames toward the Root Bridge, or from
the Root Bridge onto the network segment. When data passes from one end
station to another across a bridged local area network, it is forwarded through the
Designated Bridge/Port for each network segment towards the Root Bridge,
which in turn forwards frames towards Designated Bridges/Ports on its opposite
side.
During the Root Bridge selection process, all bridges on the network
communicate STA information via Bridge Protocol Data Units (BPDUs). It is with
BPDUs that the bridges collectively determine the current network topology and
ensure that all bridges have current topology information.
The Spanning Tree Protocol window displays information used by the network
bridges to select the Root Bridge and parameters that affect the bridge’s
participation in Spanning Tree operations.
To open the Spanning Tree Protocol window:
1. Click on the Front Panel button.
2. Drag down to Spanning Tree and release.
Figure 3-11. Spanning Tree Protocol Window