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VLANs are logical subgroups with a Local Area Network (LAN) which
combine user stations and network devices into a single unit, regardless
of the physical LAN segment to which they are attached. VLANs allow
network traffic to flow more efficiently within subgroups. VLANs use
software to reduce the amount of time it takes for network changes,
additions, and moves to be implemented. VLANs restrict traffic within the
VLAN.
VLANs have no minimum number of ports, and can be created per unit,
per device, or through any other logical connection combination, since
they are software-based and not defined by physical attributes.
VLANs function at Layer 2. Since VLANs isolate traffic within the VLAN, a
Layer 3 router is required to allow traffic flow between VLANs. Layer 3
routers identify segments and coordinate with VLANs. VLANs are
Broadcast and Multicast domains. Broadcast and Multicast traffic is
transmitted only in the VLAN in which the traffic is generated.
VLAN tagging provides a method of transferring VLAN information
between VLAN groups. VLAN 1is the default VLAN. All ports are
members of VLAN 1 by default. If the untagged port is moved to a new
VLAN, the port is removed from VLAN 1. For example: If an untagged
port 24 is moved to VLAN 5, the port will no longer be a member of
VLAN 1. However, if the port is added to VLAN 5 as a tagged port it then
remains untagged in VLAN 1.
This section contains the following topics:
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Viewing VLAN Details
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Viewing VLAN Port Details
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Creating VLANs
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Renaming VLANs
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Modifying VLAN Settings
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Modifying Port VLAN Settings
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Removing VLANs