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A Broadcast Storm is a result of an excessive amount of broadcast messages simultaneously transmitted across a network
by a single port. Forwarded message responses are heaped onto the network, straining network resources or causing the
network to time out. Storm control is enabled for all Gigabit ports by dening the packet type and the rate the packets are
transmitted. The system measures the incoming Broadcast and Multicast frame rates separately on each port, and discards
the frames when the rate exceeds a user-dened rate. The Storm Control Page provides elds for conguring broadcast
storm control.
To enable storm control for a port:
1. Click System > Network Security > Trafc Control > Storm Control. The Storm Control Page opens:
Figure 51: Storm Control Page
The Storm Control Page contains the following elds:
Port — Indicates the type of storm control which is
enabled on the selected port. The possible eld values
are:
– U, cast B, cast M — tbd
– B, cast M, cast — tbd
– B, cast — tbd
Enable Broadcast Control — Indicates if forwarding
Broadcast packet types on the interface.
Broadcast Mode — Species the Broadcast mode currently enabled on the device. The possible eld values are:
– Unknown Unicast, Multicast & Broadcast — Counts Unicast, Multicast, and Broadcast trafc.
– Multicast & Broadcast — Counts both Broadcast and Multicast trafc together.
– SOHO Broadcast — Counts only the Broadcast trafc.
Broadcast Rate Threshold — Indicates the maximum rate (kilobytes per second) at which unknown packets are
forwarded. The range is 0-1,000,000. The default value is zero. All values are rounded to the nearest 64 Kbps. If the eld
value is under 64 Kbps, the value is rounded up to 64 Kbps, with the exception of the value zero.
2. Click next to the port to congure. The Storm Control Settings Page opens:
Figure 52: Storm Control Settings Page
3. Select the Port Storm Control Settings.
4. Click Enable Broadcast Control, and define the Rate
Threshold.
5. Click . Storm control is enabled on the device
for the selected port.