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traffic to the same VLAN(s), either manually or dynamically using
GVRP. However, if you want a port on this switch to participate in
one or more VLANs, but none of the intermediate network devices
nor the host at the other end of the connection supports VLANs,
then you should add this port to the VLAN as an untagged port.
Note: VLAN-tagged frames can pass through VLAN-aware or
VLAN-unaware network interconnection devices, but
should not be used for any end-node host that does not
support VLAN tagging.
VLAN Classification – When the switch receives a fram e, it
classifies the frame in one of two ways. If the frame is untagged,
the switch assigns the frame to an associated VLAN (based on the
PVID of the receiving port). But if the frame is tagged, the switch
uses the tagged VLAN ID to identify the port broadcast domain of
the frame.
Port Overlapping – Port overlapping can be used to allow access
to commonly shared network resources among different VLAN
groups, such as file servers or printers. Note that if you implement
VLANs which do not overlap, but still need to communicate, you
can connect them by using a Layer-3 router or switch.
Untagged VLANs – Untagged (or static) VLANs are typically used
to reduce broadcast traffic and to increase security. A group of
network users assigned to a VLAN form a broadcast domain that is
separate from other VLANs configured on the switch. Packets are
forwarded only between ports that are designated for the same
VLAN. Untagged VLANs can be used to manually isolate user
groups or subnets. However, you should use IEEE 802.3 tagged
VLANs with GVRP whenever possible to fully automate VLAN
registration.