IEEE 802.1Q VLAN
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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 255 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 connect ion 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-nod e
host that does not support VLAN tagging.