ZyXEL Communications NetAtlas, User Manual

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Chapter 14 Switch Configuration
NetAtlas EPON Manager User’s Guide
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The following table describes the labels in this screen.
Table 86 Switch Configuration > STP: (M)RSTP
LABEL DESCRIPTION
Spanning
Tree
Protocol You can activate one of the STP modes on the device.
Select RSTP, MRSTP or MSTP.
Apply Click Apply to save your changes in this section.
Enable RSTP Select this check box to activate RSTP.
This field is available only when you select RSTP in the Spanning Tree
Protocol field.
Active Select this check box to activate an STP tree.
This field is available only when you select MRSTP in the Spanning Tree
Protocol field.
Tree 1/2 This is a read only index number of the STP trees.
This field is available only when you select MRSTP in the Spanning Tree
Protocol field.
Bridge
Priority Bridge priority is used in determining the root device, root port and
designated port. The device with the highest priority (lowest numeric
value) becomes the RSTP root device. If all devices have the same priority,
the device with the lowest MAC address will then become the root device.
The allowed range is 0 to 61440 (32768 is the default).
The lower the numeric value you assign, the higher the priority for this
bridge.
Bridge Priority determines the root bridge, which in turn determines Max
Age, Hello Time, and Forward Delay.
Hello Time
(sec) This is the time interval in seconds between BPDU (Bridge Protocol Data
Units) configuration message generations (by all devices in RSTP or the
root device in STP). The allowed range is 1 to 10 seconds (2 is the default).
Forward
Delay (sec) This is the maximum time (in seconds) a device will wait before changing
states. This delay is required because every device must receive
information about topology changes before it starts to forward frames. In
addition, each port needs time to listen for conflicting information that
would make it return to a blocking state; otherwise, temporary data loops
might result. The allowed range is 4 to 30 seconds (15 is the default).
Port This field displays the Ethernet port number.
Enable Select this check box to activate (M)RSTP on this port.
Priority Configure the priority for each port here.
Priority decides which port should be disabled when more than one port
forms a loop in a switch. Ports with a higher priority numeric value are
disabled first. The allowed range is between 0 and 255 and the default
value is 128.
Path Cost Path cost is the cost of transmitting a frame on to a LAN through that port.
It is recommended to assign this value according to the speed of the
bridge. The slower the media, the higher the cost.