Overview of the Spanning Tree Protocol 7-3If the link through Bridge C fails, as shown in Figure 7-3, the STPsystem reconfigures the network so that traffic from segment 2 flowsthrough Bridge B.Figure 7-3 Traffic flowing through Bridge BHow STP Works STP has the following three stages of operation:n Initializationn Stabilizationn ReconfigurationInitializationInitially, the STP system requires the following before it can configurethe network:n All bridges exchange information by way of Bridge Protocol DataUnits (BPDUs), which are transmitted in packets with a knownmulticast addressn To determine a single root bridge as a result of BPDU exchangeThe Root Bridge is selected on the basis of it having the lowest BridgeIdentifier value. This value is a combination of the unique MAC addressof the bridge and a priority component defined for the bridge.
