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ZyXEL Communications ZyXEL Dimension ES-2024 User Manual

Page 88

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Dimension ES-2024 Ethernet Switch

9-6

Spanning Tree Protocol

Table 9-4 Spanning Tree Protocol: Configuring

LABEL DESCRIPTION

Max Age

This is the maximum time (in seconds) a switch can wait without receiving a BPDU before
attempting to reconfigure. All switch ports (except for designated ports) should receive BPDUs at
regular intervals. Any port that ages out STP information (provided in the last BPDU) becomes the
designated port for the attached LAN. If it is a root port, a new root port is selected from among the
switch ports attached to the network. The allowed range is 6 to 40 seconds.

Forwarding
Delay

This is the maximum time (in seconds) a switch will wait before changing states. This delay is
required because every switch 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.

As a general rule:

2 * (Forward Delay - 1) >= Max Age >= 2 * (Hello Time + 1)

Port

This field displays the port number.

Active

Select this check box to activate STP 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 default value is 128.

Path Cost

Path cost is the cost of transmitting a frame on to a LAN through that port. It is assigned according
to the speed of the bridge. The slower the media, the higher the cost - see Table 9-1 for more
information.

Apply Click

Apply to save your changes back to the switch.

Cancel Click

Cancel to begin configuring this screen afresh.