D-Link xStack DES-3800 Series, Руководство пользователя

Страница: 215 / 360

xStack DES-3800 Series Layer 3 Stackable Fast Ethernet Managed Switch
Section 11
Security
Traffic Control
Port Security
Port Lock Entries
802.1X
Trusted Host
Access Authentication Control
Traffic Segmentation
SSL
SSH
IP MAC Binding
Limited IP Multicast Range Settings
Web-based Access Control
MAC-based Access Control
Safeguard Engine
Traffic Control
Figure 6- 53. Traffic Control Table window
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 the following window to configure Traffic Control, click
Security > Traffic Control .
200