User’s Manual of FSD-804PS
4.6.1 802.1p Tag Priority Mode
QoS settings allow customization of packet priority in order to facilitate delivery of data traffic that might be affected by
latency problems. When 802.1p Tag Priority is applied, the PoE Switch recognizes 802.1Q VLAN tag packets and extracts
the VLAN tagged packets with User Priority value.
802.1Q Tag and 802.1p priority
User Priority
CFI
VLAN ID (VID)
3 bits
1 bits
12 bits
TPID (Tag Protocol Identifier)
TCI (Tag Control Information)
2
bytes
2
bytes
Preamble
Destination
Address
Source Ad-
dress
VLAN TAG
Ethernet
Type
Data FCS
6 bytes
6 bytes
4 bytes
2 bytes
46-1517 bytes
4 bytes
Figure 4-36
802.1p Tag Priority
The IEEE 802.1p Tag Priority specification uses 2 priority levels to classify data packets. The screen in
Figure 4-37
ap-
pears.
Figure 4-37
QoS - 802.1p Tag Priority screen
The page includes the following fields:
•
Object
•
Description
•
QoS Mode
The draw menu allows customization of QoS mode for Traffic classifiers.
•
802.1p Tag Priority
•
IP
DSCP
•
Port-Base
Priority
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