LevelOne GTL-2881, User Manual

Page: 154 / 706

Chapter 5
| VLAN Configuration
IEEE 802.1Q VLANs
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groups (such as e-mail), or multicast groups (used for multimedia applications such
as video conferencing).
VLANs provide greater network efficiency by reducing broadcast traffic, and allow
you to make network changes without having to update IP addresses or IP subnets.
VLANs inherently provide a high level of network security since traffic must pass
through a configured Layer 3 link to reach a different VLAN.
This switch supports the following VLAN features:
◆
Up to 4094 VLANs based on the IEEE 802.1Q standard
◆
Distributed VLAN learning across multiple switches using explicit or implicit
tagging and GVRP protocol
◆
Port overlapping, allowing a port to participate in multiple VLANs
◆
End stations can belong to multiple VLANs
◆
Passing traffic between VLAN-aware and VLAN-unaware devices
◆
Priority tagging
Assigning Ports to VLANs
Before enabling VLANs for the switch, you must first assign each port to the VLAN
group(s) in which it will participate. By default all ports are assigned to VLAN 1 as
untagged ports. Add a port as a tagged port if you want it to carry traffic for one or
more VLANs, and any intermediate network devices or the host at the other end of
the connection supports VLANs. Then assign ports on the other VLAN-aware
network devices 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 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 the VLAN tags should be stripped off before
passing it on to any end-node host that does not support VLAN tagging.