Planex FMG-24K, Руководство пользователя

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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 endstation (or its network adapter)
supports the IEEE 802.1Q VLAN protocol, it can be configured to broadcast a
message to your network indicating the VLAN groups it wants to join. When this
switch receives these messages, it will automatically place the receiving port in
the specified VLANs, and then forward the message to all other ports. When the
message arrives at another switch that supports GVRP, it will also place the
receiving port in the specified VLANs, and pass the message on to all other
ports. VLAN requirements are propagated in this way throughout the network.
This allows GVRP-compliant devices to be automatically configured for VLAN
groups based solely on endstation requests.
To implement GVRP in a network, you must first configure the static VLANs
required on switches that are connected to PCs, servers, and other devices, so
that these VLANs can be propagated across the network (Web - VLAN / VLAN
Membership). For other core switches in the network, enable GVRP on the links
between these devices (Web - VLAN / Port Settings or Trunk Settings). You
should also determine security boundaries in the network and disable GVRP on
ports to prevent advertisements being propagated, or forbid ports from joining
restricted VLANs.
Forwarding Tagged/Untagged Frames
If you want to create a small port-based VLAN for devices attached directly to a
single switch, you can assign ports to the same untagged VLAN. However, to
participate in a VLAN group that crosses several switches, you need to create a
VLAN for that group and enable tagging on all ports.
Ports can be assigned to multiple tagged or untagged VLANs. Each port on the
switch is therefore capable of passing tagged or untagged frames. To forward a
frame from a VLAN-aware device to a VLAN-unaware device, the switch first
decides where to forward the frame, and then strips off the VLAN tag. However,
to forward a frame from a VLAN-unaware device to a VLAN-aware device, the
switch first decides where to forward the frame, and then inserts a VLAN tag
reflecting this port’s default VID.
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