DES-1218R/DES-1226R 10/100/1000 Mbps Ethernet Switch User ’s Guide
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When
Auto
is chosen, NWay will negotiate three settings:
♦
Speed – 10/100/1000
♦
Duplex - Full/Half
♦
IEEE 802.3x Flow Control –
Enable
/
Disable
Flow Control
Toggles flow control
Enable
or
Disable
. It is useful during periods of heavy network activity when
the Switch’s buffers can receive too much traffic and fill up faster than the Switch can forward the
information. In such cases, the Switch will intervene and tell the transmitting device to pause to
allow the information in the port buffer to be sent. The flow control default setting is
Enable
.
Port Trunk Groups
The Switch supports the use of port trunk groups. Each trunk group may contain 2 to 4 ports as
members for a potential bit rate of up to 800 Mbps per trunk group. See the discussion of
Port
Trunk Groups
in Chapter 6 for more detailed information about port trunk groups.
Port Mirroring
Allows you to select a port to monitor activity for analysis. The monitored port will mirror all
activity to that port. This feature is useful for analyzing traffic in ports where acute traffic
congestion or other problems may exist.
Priority Queues
This feature allows you to customize packet traffic handling to the particular needs of your network.
Configure this setting for packets passing through the port, using IEEE 802.1p priority tagging.
These settings are universal, that is, they are for all ports on the Switch. Four priority levels may be
assigned with Queue 3 being the highest priority queue, and Queue 0 being the lowest priority queue.
Note:
The settings you assign to the queues, numbers 0-7, represent the IEEE 802.1p priority tag
number. Do not confuse these settings with port numbers.
The highest
priority queue, Queue 3, should reserved for data in which latency can have adverse
affects on the function of an application, such as video or audio data, where latency can produce
distorted sounds and images.
Packets in the
lower priority queues
will be processed with less
urgency.
See the discussion on
IEEE 802.1p
Priority
and management of priority queues in
Chapter 6.
Figure 5-2 shows how priority queues might be assigned. Access the Priority Queue settings on the
third page of the console management screen
