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The picture above shows the default priority setting for the Switch. Class-3 has the highest priority of the four priority
queues on the Switch. In order to implement QoS, the user is required to instruct the Switch to examine the header of a
packet to see if it has the proper identifying tag tagged. Then the user may forward these tagged packets to designated
queues on the Switch where they will be emptied, based on priority.
"The DUT support strict mode for 802.1p QoS. The untagged pkt will follow the priority 0 to work (i.e. class 1)."
Understanding QoS
The Switch has four priority queues. These priority queues are labeled as 3, the high queue to 0, the lowest queue. The
eight priority tags, specified in IEEE 802.1p are mapped to the Switch's priority tags as follows:
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Priority 0 is assigned to the Switch's Q1 queue.
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Priority 1 is assigned to the Switch's Q0 queue.
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Priority 2 is assigned to the Switch's Q0 queue.
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Priority 3 is assigned to the Switch's Q1 queue.
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Priority 4 is assigned to the Switch's Q2 queue.
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Priority 5 is assigned to the Switch's Q2 queue.
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Priority 6 is assigned to the Switch's Q3 queue.
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Priority 7 is assigned to the Switch's Q3 queue.
The Switch uses strict priority for Scheduling. Strict priority-based scheduling, any packets residing in the higher priority
queues are transmitted first.
D-Link's Green Technology
D-Link's Green Technology implements special power-saving features under speed at 1000Mbps that detect cable length
and link status and adjust power usage accordingly.
Further, D-Link Green implement the newly ratified IEEE 802.3az Energy Efficient Ethernet standard for reducing energy
consumption of network links during periods of low utilization by transitioning interfaces into low-power state without
interrupting the network connection.
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IEEE 802.3az Energy-Efficient Ethernet (EEE):
It is the first standard in the history of Ethernet to address proactive reduction in energy consumption for networked
devices. The IEEE 802.3 EEE standard defines mechanisms and protocols intended to reduce the energy consumption
of network links during periods of low utilization, by transitioning interfaces into a low-power state without
interrupting the network connection.
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Power Saving Technology:
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Power saving by link status.
If there is no link on a port, such as when there is no computer connected to the port or the connected computer is
powered off, D-Link's Green Technology will enter a "sleep mode", drastically reducing power used for that port.
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Power saving by cable length: 0~20m, 21 ~100m.
D-Link's Green Technology detects the length of connected Ethernet cable and adjusts power usage accordingly
without affecting performance. This way, a port connected to a less than 20m cable only uses as much power as it
needs, instead of using full power, which is only needed for 100m cables.
D-Link DGS-1005D Unmanaged Gigabit Ethernet Switch
Mapping QoS on the Switch
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