Operation Manual

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1. ACCESS: The ACCESS port can be added in a single VLAN, and the egress rule of the port
is UNTAG. The PVID is same as the current VLAN ID. If the ACCESS port is added to another
VLAN, it will be removed from the current VLAN automatically.
2. TRUNK: The TRUNK port can be added in multiple VLANs, and the egress rule of the port is
TAG. The TRUNK port is generally used to connect the cascaded network devices for it can
receive and forward the packets of multiple VLANs. When the packets are forwarded by the
TRUNK port, its VLAN tag will not be changed.
3. GENERAL: The GENERAL port can be added in multiple VLANs and set various egress rules
according to the different VLANs. The default egress rule is UNTAG. The PVID can be set as
the VID number of any VLAN the port belongs to.

PVID
PVID (Port VLAN ID) is the default VID of the port. When the switch receives an
un-VLAN-tagged packet, it will add a VLAN tag to the packet according to the PVID of its
received port and forward the packets.
When creating VLANs, the PVID of each port, indicating the default VLAN to which the port
belongs, is an important parameter with the following two purposes:
1. When the switch receives an un-VLAN-tagged packet, it will add a VLAN tag to the packet
according to the PVID of its received port
2. PVID determines the default broadcast domain of the port, i.e. when the port receives UL
packets or broadcast packets, the port will broadcast the packets in its default VLAN.
Different packets, tagged or untagged, will be processed in different ways, after being received
by ports of different link types, which is illustrated in the following table.
Port Type
Receiving Packets
Forwarding Packets
Untagged Packets
Tagged Packets
Access
When untagged
packets are
received, the port will
add the default VLAN
tag, i.e. the PVID of
the ingress port, to
the packets.
If the VID of packet is the
same as the PVID of the
port, the packet will be
received.
If the VID of packet is not
the same as the PVID of
the port, the packet will
be dropped.
The packet will be forwarded
after removing its VLAN tag.
Trunk
If the VID of packet is
allowed by the port, the
packet will be received.
If the VID of packet is
forbidden by the port,
the packet will be
dropped.
The packet will be forwarded
with its current VLAN tag.
General
If the egress rule of port is TAG,
the packet will be forwarded with
its current VLAN tag.
If the egress rule of port is
UNTAG, the packet will be
forwarded after removing its
VLAN tag.