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3. Virtual LAN Configuration
This chapter contains the following topics:
• VLAN Overview
• Port-Based Configuration
• 802.1Q Based Configuration
VLAN Overview
Virtual LANs are made up of networked devices grouped together logically into separate
networks. You can group ports on a switch to create a virtual network made up of the devices
connected to the ports. VLANs can be grouped using Port-Based or 802.1Q criteria.
Port Based. Allows you to assign ports to virtual networks. Data from a port that is a member
of a VLAN group is restricted to other members of that VLAN group. This is an easy way to
partition a network into private sub networks.
802.1Q. Allows you to create virtual networks using 802.1Q criteria. When using 802.1Q
VLAN configuration, you configure ports to be a part of a VLAN group. When a port receives
data tagged for a VLAN group, the data is discarded unless the port is a member of the
VLAN group. This technique is useful to communicate with devices outside of your local
network as well as still receiving data from other ports not in your VLAN group. It requires
that you know the VLAN group IDs used.