Interlogix GE-DSSG-244, User Manual

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IFS NS3601-24P/4S GE-DSSG-244 and 244-POE User Manual
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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 favor 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).
Default:
128
Range: 0-240, in steps of 16
•
operEdge (state flag)
Operational flag describing whether the port is connecting directly to edge
devices. (No Bridges attached). Transitioning to the forwarding state is faster for
edge ports (having operEdge true) than for other ports.
•
AdminEdge
Controls whether the operEdge flag should start as beeing 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 influencing the
spanning tree active topology, possibly because those bridges are not under the
full control of the administrator. This feature is also know 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 trees active topology as a result
of persistent incorrectly 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 is the physical link state for the attached LANs
transitions 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 effect this setting.
A port entering error-disabled state due to this setting is subject to the bridge Port
Error Recovery setting as well.
•
Point2Point
Controls whether the port connects to a point-to-point LAN rather than a shared
medium. This can be automatically determined, or forced either true or false.
Transitions to the forwarding state is faster for point-to-point LANs than for
shared media.
(This applies to physical ports only. Aggregations are always
forced Point2Point
).
Buttons
: Click to save changes.
: Click to undo any changes made locally and revert to previously saved values.
By default, the system automatically detects the speed and duplex mode used on each port, and configures the path cost according
to the values shown below. Path cost “0” is used to indicate auto-configuration mode. When the short path cost method is selected
and the default path cost recommended by the IEEE 8021w standard exceeds 65,535, the default is set to 65,535.
Port Type IEEE 802.1D-1998 IEEE 802.1w-2001
Ethernet
50-600 200,000-20,000,000
Fast Ethernet
10-60 20,000-2,000,000
Gigabit Ethernet
3-10 2,000-200,000
Table 4-7-1
Recommended STP Path Cost Range