Gigabit Ethernet Switch Management Guide

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traffic, but also 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 Layer
3 switch or a router to reach a different VLAN.
This switch supports the following VLAN features:
• Up to 256 VLANs based on the IEEE 802.1Q standard
• Distributed VLAN learning across multiple switches using
explicit or implicit tagging
• 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
• Port trunking with VLANs
Assigning Ports to VLANs
Before enabling VLANs for the switch, you must first assign each
port to the VLAN group(s) it will participate in. (By default all ports
are assigned to VLAN 1 as untagged ports.) Add a port as a tagged
port (that is, a port attached to a VLAN-aware device) if you want it
to carry traffic for one or more VLANs and the device at the other
end of the link also supports VLANs. Then assign the port at the
other end of the link to the same VLAN(s). However, if you want a
port on this switch to participate in one or more VLANs, but the
device at the other end of the link does not support VLANs, then you
must add this port as an untagged port (that is, a port attached to a
VLAN-unaware device).
Port-based VLANs are tied to specific ports. The switch’s forwarding
decision is based on the destination MAC address and its associated