Chapter 6: Configuring Vlans - Linksys SFE2000 Reference Manual

Configuring VLANs
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 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 working at
a protocol level 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
tagging attaches a 4-byte tag to packet headers. The VLAN tag indicates to which VLAN the packets
belong. VLAN tags are attached to the VLAN by either the end station or the network device. VLAN
tags also contain VLAN network priority information.
Combining VLANs and GARP (Generic Attribute Registration Protocol) allows network managers to
define network nodes into Broadcast domains. The VLAN Management section contains the following
pages:
• Defining VLAN Properties
• Defining VLAN Membership
• Defining Interface Settings
• Configuring GVRP Settings
Chapter 6:
SFE2000/SFE2000P Gigabit Ethernet Switch Reference Guide
Chapter
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