52 C HAPTER 4: C ONFIGURING THE SWITCH F ROM T HE WEB I NTERFACEtree network. The bridging device, known as the RootBridge, generates bridge protocol data units (BPDUs) onall ports at a regular interval, known as the Hello Time.All other spanning tree-compliant devices on thenetwork have a designated Root Port. This is the Portnearest the Root Bridge and it is used for receiving theBPDUs initiated by the Root Bridge. If a bridge does notget a Hello BPDU after a predetermined interval, thebridge assumes that the link to the Root Bridge isdown. This bridge will then initiate negotiations withother bridges to reconfigure the network to reestablisha valid network topology.After all the bridges on the network have determinedthe configuration of their ports, each bridge onlyforwards traffic between the Root Port and the portsthat are the Designated Bridge Ports for each networksegment. All other ports are blocked, which means thatthey are prevented from forwarding traffic.Three tabs are available on the Spanning Tree page:■ Summary■ Setup■ Port SetupSummaryUse the Summary tab to display Status, Edged Port, LinkType, Path Cost, State, or Port Priority for all the ports.Figure 40 Spanning Tree Summary Screen
