TRENDnet TPE-4840WS User Manual page 30

TRENDnet User's Guide
Note: Click Apply in the end of the row to apply the change.
BPDU pass-through must be disabled for all ports under
Physical interface for STP can be enabled.
Priority: Indicates the port priority. If two paths have the
same port cost, the bridges must select a preferred
path. In some instances this can involve the use of
the port priority parameter which is used as a tie
breaker when two paths have the same cost.
The range for port priority is 0 to 240. As with
bridge priority, this range is broken into
increments, in this case multiples of 16. To select a
port priority for a port, select a desired value.
Note: Click Apply in the end of the row to apply the change.
If you select Ignore on All Ports and click on Apply for all
ports, the Admin Cost setting is not changing. If you set the
value then click on Apply for all ports, The Admin Cost will
be set to the same value.
Admin Cost
The administratively assigned value for the
(0 = Auto):
contribution of this port to the path cost of a port.
Writing a value of '0' assigns the automatically
calculated default path cost value to the port. If the
default path cost is being used, this object returns '0'
when read.
External Cost: This defines a metric that indicates the relative cost
of forwarding packets to the specified port list. Port
cost can be set automatically or as a metric value.
Define a value between 1 and 200,000,000 to
determine the external cost. The default port cost:
100Mbps port = 200,000. Gigabit port = 20,000.
State: Displays the current port spanning tree state.
 Blocking: A blocking state does not allow
network traffic to be sent or received on the port
except for BPDU data. A port with a higher path
cost to the root bridge than another on the switch
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causes a switching loop and is placed in the
blocking state by the Spanning Tree algorithm.
The port's state may change to the forwarding
state if the other links in use fail and the Spanning
Tree algorithm determines the port may
transition to the forwarding state.
 Listening: This state occurs on a port during the
convergence process. The port in the listening
state processes BPDUs
information that would cause the port to return to
the blocking state.
 Learning: While the port does not yet forward
frames (packets), in this state the port does learn
source addresses from frames received and adds
them to the filtering (switching) database.
 Forwarding: A port that both receives and sends
data. This indicates normal operation. STP
continues to monitor the port for incoming BPDUs
that indicate the port should return to the
blocking state to prevent a loop.
 Disabled: A port with STP disabled does not
participate in STP. A network administrator can
manually disable a port.
Edge: Indicates if a port is connected to an edge device in
the network topology or not. Selecting the
ForceTrue to assign the port as an edge port. Edge
ports cannot create loops, however an edge port can
lose edge port status if a topology change creates a
potential for a loop. An edge port normally should
not receive BPDU packets. If a BPDU packet is
received, it automatically loses edge port status.
Selecting the ForceFalse indicates that the port
does not have edge port status. Selecting the Auto
parameter indicates that the port have edge port
TPE-4840WS
and awaits new
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