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ONFIGURATION
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along the path that will carry this 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 t he 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 the VLAN
tags should be stripped off before passing it on to an y end-node
host that does not support VLAN tagging.
VLAN Classification – When the switch receives a frame, 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 VLANs – Untag ged (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 configure d on the switch. Packets are
forwarded only between ports that are designated for the same VLAN.
Untagged VLANs can be used to manually isolat e user groups or subnets.
However, you should use IEEE 802.3 tagged VLANs with GVRP
whenever possible to fully automate VLAN registration.
Automatic VLAN Registration – GVRP (GARP VLAN Registration
Protocol) defines a system whereby the switch can automatically learn the
VLANs to which each endstation should be assigned. If an endsta tion (or
its network adapter) supports the IEEE 802.1Q VLAN protocol, it can be