3Com 3C16476CS - Manual (Page 48)

48 C HAPTER 4: C ONFIGURING THE S WITCH
the Root Bridge generates BPDUs (Bridge Protocol
Data Units) on all ports at a regular interval known as
the Hello Time. All other spanning tree-compliant
devices on the network have a designated Root Port.
This is the Port nearest the Root Bridge and it is used
for receiving the BPDUs initiated by the Root Bridge. If
a bridge does not get a Hello BPDU after a
predetermined interval, the bridge assumes that the
link to the Root Bridge is down. This bridge will then
initiate negotiations with other bridges to reconfigure
the network to re-establish a valid network topology.
After all the bridges on the network have determined
the configuration of their ports, each bridge only
forwards traffic between the Root Port and the ports
that are the Designated Bridge Ports for each network
segment. All other ports are blocked, which means
that they are prevented from forwarding traffic.
Three tabs are available on the Spanning Tree per Port
page:
■ Summary
■ Detail
■ Setup
Summary
Use the Summary tab to display Status, Edged Port,
Link Type, Path Cost, State, or Port Priority for all the
ports.
Figure 45 Spanning Tree Summary Screen
Detail
Use the Detail tab to display detailed spanning tree
information for a port.