Viewing the Current Spanning Tree Configuration
Device Control Menu Screens
7-17
Parameter
Description
Status
Displays the current state of this port within the spanning
tree:
Disabled – Port has been disabled by the user or has failed
diagnostics.
Blocking – Port receives STA configuration messages, but
does not forward packets.
Listening – Port will leave blocking state due to topology
change, starts transmitting configuration messages, but does
not yet forward packets.
Learning – Has transmitted configuration messages for an
interval set by the Forward Delay parameter without
receiving contradictory information. Port address table is
cleared, and the port begins learning addresses.
Forwarding – The port forwards packets, and continues
learning addresses.
The rules defining port status are:
•
A port on a network segment with no other STA
compliant bridging device is always forwarding.
•
If two ports of a switch are connected to the same
segment and there is no other STA device attached to this
segment, the port with the smaller ID forwards packets
and the other is blocked.
•
All ports are blocked when the switch is booted, then
some of them change state to listening, to learning, and
then to forwarding.
Forward Transitions
Number of frames forwarded out the port.
Designated Cost
The cost for a packet to travel from this port to the root in
the current spanning tree configuration. The slower the
media, the higher the cost.
