User Manual
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(Figure 5.6.2.2)
5.7 L2 Features
5.7.1 VLAN
The product supports based on 802.1Q VLAN. It deals with messages based on Tag of recognized
message(including 802.1p priority and VLAN ID, etc.)
Frames with 802.1q add 4 byte Tag based on Ethernet frames, including 2 byte TPID, 3 byte Priority,
1 byte CFI and 12 byte VLAN ID.
TPID:
a 16-bit field set to a value of 0x8100 in order to identify the frame as an IEEE 802.1Q-tagged
frame.
Priority:
It indicates the frame priority level. Values are from 0 (best effort) to 7 (highest); 1 represents
the lowest priority.
CFI:
a 1-bit field. If the value of this field is 1, the MAC address is in non-canonical format. If the value is
0, the MAC address is in canonical format.
VLAN ID:
a 12-bit field specifying the VLAN to which the frame belongs. The hexadecimal values of
0x000 and 0xFFF are reserved. All other values may be used as VLAN identifiers, allowing up to 4,094
VLAN.
1. The type of port’s Line
The product support 2 type port line:
Access:
Port belongs to 1 VLAN, normally, it used for connecting user device, default all port is access
port.
Trunk:
Port belongs to some VLAN, can transmit and receive some VLAN message, normally, it used
for connection of network device.
2.
Deal with transmit and receive message
Type
Receive message
Message did not take Tag
Message take Tag
