VLAN C
ONFIGURATION

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VLAN Configuration
In conventional networks with routers, broadcast traffic is split up into
separate domains. Switches do not inherently support broadcast domains.
This can lead to broadcast storms in large networks that handle traffic
such as IPX or NetBeui. By using IEEE 802.1Q-compliant VLANs, you
can organize any group of network nodes into separate broadcast domains,
thus confining broadcast traffic to the originating group. This also
provides a more secure and cleaner network environment.
An IEEE 802.1Q VLAN is a group of ports that can be located anywhere
in the network, but communicate as though they belong to the same
physical segment.
VLANs help to simplify network management by allowing you to move
devices to a new VLAN without having to change any physical
connections. VLANs can be easily organized to reflect depar tmental
groups (such as Marketing or R&D), usage groups (such as e-mail), or
multicast groups (used for multimedia applications such as
videoconferencing.)
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.
• 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
• Priority tagging