Installation manual

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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 enabled routing on this 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.
Automatic VLAN Registration – GVRP (GARP VLAN Registration Protocol) defines a
system whereby the switch can automatically learn the VLANs to which each end station
should be assigned. If an end station (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, first add the host devices to the required VLANs (using
the operating system or other application software), so that these VLANs can be
propagated onto the network. For both the edge switches attached directly to these hosts,
and core switches in the network, enable GVRP on the links between these devices. You
should also determine security boundaries in the network and disable GVRP on the
boundary ports to prevent advertisements from being propagated, or forbid those ports
from joining restricted VLANs.