Chapter 7: Configuring Vlans - Cisco ESW 500 Administration Manual

Configuring VLANs
Configuring VLANs
ESW 500 Series Switches Administration Guide
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 Generic Attribute Registration Protocol (GARP) allows
network managers to define network nodes into Broadcast domains. The VLAN
Management section contains the following topics:
This section contains the following topics:
•
Defining VLAN Properties
•
Defining VLAN Membership
•
Assigning Ports to Multiple VLANs
•
Defining Interface Settings
•
Defining GVRP Settings
•
Defining Protocol Groups
•
Defining a Protocol Port
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