ZyXEL Communications XGS3600 Series Manual page 93

Parameter description:
Port :

The switch port number of the logical STP port.
STP Enabled :

Controls whether STP is enabled on this switch port.
Path Cost :

Controls the path cost incurred by the port. The Auto setting will set the path
cost as appropriate by the physical link speed, using the 802.1D recommended
values. Using the Specific setting, a user-defined value can be entered. The
path cost is used when establishing the active topology of the network. Lower
path cost ports are chosen as forwarding ports in favour of higher path cost
ports. Valid values are in the range 1 to 200000000.
Priority :

Controls the port priority. This can be used to control priority of ports having
identical port cost. (See above).
operEdge (state flag) :

Operational flag describing whether the port is connecting directly to edge
devices. (No Bridges attached). Transition to the forwarding state is faster for
edge ports (having operEdge true) than for other ports.The value of this flag is
based on AdminEdge and AutoEdge fields. This flag is displayed as Edge in
Monitor->Spanning Tree -> STP Detailed Bridge Status.
AdminEdge :

Controls whether the operEdge flag should start as set or cleared. (The initial
operEdge state when a port is initialized).
AutoEdge :

Controls whether the bridge should enable automatic edge detection on the
bridge port. This allows operEdge to be derived from whether BPDU's are
received on the port or not.
Restricted Role :

If enabled, causes the port not to be selected as Root Port for the CIST or any
MSTI, even if it has the best spanning tree priority vector. Such a port will be
selected as an Alternate Port after the Root Port has been selected. If set, it
can cause lack of spanning tree connectivity. It can be set by a network
administrator to prevent bridges external to a core region of the network
influence the spanning tree active topology, possibly because those bridges are
not under the full control of the administrator. This feature is also known as
Root Guard.
Restricted TCN :

If enabled, causes the port not to propagate received topology change
notifications and topology changes to other ports. If set it can cause temporary
loss of connectivity after changes in a spanning tree's active topology as a
result of persistently incorrect learned station location information. It is set by
a network administrator to prevent bridges external to a core region of the
network, causing address flushing in that region, possibly because those
bridges are not under the full control of the administrator or the physical link
state of the attached LANs transits frequently.
BPDU Guard :

If enabled, causes the port to disable itself upon receiving valid BPDU's.
Contrary to the similar bridge setting, the port Edge status does not affect this
setting. A port entering error-disabled state due to this setting is subject to the
XGS3600 Series User's Guide
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