Traffic Control - D-Link DES-3528 User Manual

xStack DES-3528 Series Layer 2 Stackable Fast Ethernet Managed Switch User Manual
Click Apply to set the bandwidth control for the selected ports. Results of configured Bandwidth Settings will be
displayed in the Bandwidth Control Table on the lower half of the window.

Traffic Control

On a computer network, packets such as Multicast packets and Broadcast packets continually flood the network as
normal procedure. At times, this traffic may increase do to a malicious endstation on the network or a malfunctioning
device, such as a faulty network card. Thus, switch throughput problems will arise and consequently affect the overall
performance of the switch network. To help rectify this packet storm, the Switch will monitor and control the situation.
The packet storm is monitored to determine if too many packets are flooding the network, based on the threshold level
provided by the user. Once a packet storm has been detected, the Switch will drop packets coming into the Switch
until the storm has subsided. This method can be utilized by selecting the Drop option of the Action field in the window
below.
The Switch will also scan and monitor packets coming into the Switch by monitoring the Switch's chip counter. This
method is only viable for Broadcast and Multicast storms because the chip only has counters for these two types of
packets. Once a storm has been detected (that is, once the packet threshold set below has been exceeded), the
Switch will shutdown the port to all incoming traffic with the exception of STP BPDU packets, for a time period
specified using the CountDown field. If this field times out and the packet storm continues, the port will be placed in a
Shutdown Forever mode which will produce a warning message to be sent to the Trap Receiver. Once in Shutdown
Forever mode, the only method of recovering this port is to manually recoup it using the Port Configuration window
in the Administration folder and selecting the disabled port and returning it to an Enabled status. To utilize this
method of Storm Control, choose the Shutdown option of the Action field in the window below.
To view this table Click QoS > Traffic Control
Figure 8- 4. Traffic Control window
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