D-Link DES-3326, Руководство пользователя

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24-port NWay Ethernet Switch User’s Guide
72 Switch Management and Operating Concepts
Thus, the smaller the broadcast domain, the smaller effect a
broadcast storm will have. Because VLANs are implemented at
each switch port, they can be quite effective in limiting the scope
of broadcast storms.
Eliminating Broadcast Storms
SNMP agents can be programmed to monitor the number of
broadcast packets on switch ports and act on the data. When the
number of broadcast packets on a given port rise past an
assigned threshold, an action can be triggered. When enabled,
the usual action is to block the port from receiving broadcast
packets. This will discard all broadcast frames arriving at the
port from the attached segment. Not only does this isolate the
broadcast domain, but it actually starts removing broadcast
packets from the affected segment. When the number of
broadcast packets falls to an acceptable level (below the trigger
level), the SNMP agent can remove the blocking condition,
returning the port to its normal operational state.
In the DES-3326, the default trigger threshold is set to 128,000
broadcast packets per second (128 Kpps) for both 100 Mbps Fast
Ethernet ports and the optional 1000 Mbps Gigabit Ethernet
ports. The thresholds can be set separately for the two types of
ports and can easily be modified by using a normal SNMP
management program or through the console interface.
IP Addressing and Subnetting
This section gives basic information needed to configure your
Layer 3 switch for IP routing. The information includes how IP
addresses are broken down and how subnetting works. You will