User’s Manual of
4.9.2 QoS Configuration
QoS settings allow customization of packet priority in order to facilitate delivery of data traffic that might be affected by latency problems. When CoS / 802.1p Tag Priority is applied, the Switch recognizes 802.1Q VLAN tag packets and extracts the VLAN tagged packets with User Priority value.
802.1Q Tag and 802.1p priority
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| User Priority |
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| VLAN ID (VID) |
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| 3 bits | 1 bits |
| 12 bits |
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| TPID (Tag Protocol |
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| TCI (Tag Control |
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| Identifier) |
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| Information) |
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| 2 bytes |
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Preamble | Destination |
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| VLAN TAG |
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| Data |
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Address |
| Address |
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| 6 bytes |
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| 4 bytes |
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| 2 bytes | 4 bytes |
Figure
Set up the COS priority level. With the
4.9.2.1 Priority Queue Service settings
QoS settings allow customization of packet priority in order to facilitate delivery of data traffic that might be affected by latency problems. The IEEE 802.1p Priority specification uses 8 priority levels to classify data packets. In 802.1p compliant devices, a tag inserted into the packet header is used to identify the priority level of data packets.
The Switch supports Static Port Ingress priority and four queues. The screen in Figure
Figure
101