User Guide

Configuring Switching
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GS716Tv3, GS724Tv4, and GS748Tv5 Smart Switches
VLANs
Adding virtual LAN (VLAN) support to a Layer 2 switch offers some of the benefits of both
bridging and routing. Like a bridge, a VLAN switch forwards traffic based on the Layer 2
header, which is fast, and like a router, it partitions the network into logical segments, which
provides better administration, security, and management of multicast traffic.
By default, all ports on the switch are in the same broadcast domain. VLANs electronically
separate ports on the same switch into separate broadcast domains so that broadcast
packets are not sent to all the ports on a single switch. When you use a VLAN, users can be
grouped by logical function instead of physical location.
Each VLAN in a network has an associated VLAN ID, which displays in the IEEE 802.1Q tag
in the Layer 2 header of packets transmitted on a VLAN. An end station can omit the tag, or
the VLAN portion of the tag, in which case the first switch port to receive the packet can either
reject it or insert a tag using its default VLAN ID. A given port can handle traffic for more than
one VLAN, but it can support only one default VLAN ID.
For more information about configuring VLANs, see Virtual Local Area Network Configuration
Example on page 263.
The VLAN menu contains links described in the following sections.
• Basic VLAN Configuration
• VLAN Membership Configuration
• VLAN Status
• Port VLAN ID Configuration
• MAC-Based VLAN
• Protocol-Based VLAN Group Configuration
• Protocol-Based VLAN Group Membership
• Voice VLAN