Planet FSD-804PS User Manual page 36

Tag-aware switches must keep a table to relate PVID within the switch to VID on the network. The switch will compare the
VID of a packet to be transmitted to the VID of the port that is to transmit the packet. If the two VID are different the switch
will drop the packet. Because of the existence of the PVID for untagged packets and the VID for tagged packets, tag-aware
and tag-unaware network devices can coexist on the same network.
A switch port can have only one PVID, but can have as many VID as the switch has memory in its VLAN table to store them.
Because some devices on a network may be tag-unaware, a decision must be made at each port on a tag-aware device
before packets are transmitted – should the packet to be transmitted have a tag or not? If the transmitting port is connected
to a tag-unaware device, the packet should be untagged. If the transmitting port is connected to a tag-aware device, the
packet should be tagged.
Default VLANs
The Switch initially configures one VLAN, VID = 1, called "default." The factory default setting assigns all ports on the
Switch to the "default". As new VLAN are configured in Port-based mode, their respective member ports are removed
from the "default."
The Switch supports SVL(Shared VLAN Learning) , all VLAN groups share the same Layer
2 learned MAC address table.
1
2
No matter what basis is used to uniquely identify end nodes and assign these nodes
VLAN membership, packets cannot cross VLAN without a network device performing a
routing function between the VLAN.
The Switch supports Port-based VLAN and IEEE 802.1Q VLAN. The port untagging
function can be used to remove the 802.1 tag from packet headers to maintain com-
patibility with devices that are tag-unaware.
User's Manual of FSD-804PS
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