D-Link D-View 5.1, User Manual

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D-View 5.1 User’s Guide
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displays the number of frames that were discarded by this port due to excessive transit
delay through the bridge.
The
MtuExceedDiscards column corresponds to the Dot1dBasePort-
MtuExceededDiscards MIB object of the dot1dBase group. This read-only object
displays the number of frames that were discarded by this port due to excessive size.
The
Refresh button refreshes the table. You need to refresh the table once in a while to
ensure all updates performed on the device are reflected on this table.
Spanning Tree → Information
This command allows you to access and set MIB objects that specify the bridge state
with respect to the Spanning Tree Protocol (STP). If the bridge does not implement such
protocol, then this command becomes irrelevant.
STP is primarily for detecting and preventing network loops, which occur when multiple
paths exist between any two communicating nodes. With STP, all redundant paths are
blocked and are placed in backup mode; if the path for which there is a backup path
fails, then its backup will be automatically activated to take over the path. This feature
is particularly useful in a multibridged network where redundant path occurrences are
frequent.
The
Objects column lists the available MIB objects. For information about these
objects, see the discussion below.
The
Description column displays the current value of each displayed object.
The Refresh button refreshes the table. You need to refresh the table once in a while to
ensure all updates performed by other network administrators on the displayed objects
are reflected on this table. Be reminded that you are not the only one managing the
device.
The
Set button sets MIB objects with read-write attributes. The following describes the
various MIB objects displayed on the above table:
The
Protocol object corresponds to the Dot1dStpProtocolSpecification MIB object of the
dot1dStp group. This read-only object indicates the STP version implemented on the
bridge. An “ieee8021d(3)” value means that the STP version is IEEE 802.1d.
The
Priority object corresponds to the Dot1dStpPriority MIB object of the dot1dStp
group. This read-write object displays the priority number of the bridge. This value is
used in conjunction with the bridge MAC address to set the bridge ID that in turn is
used when determining the root bridge of a multibridged network. The root bridge is
responsible for processing data packets when network loops occur on the network.