Configuring Vlans - 3Com 3CRUS2475 User Manual

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ONFIGURING
This section contains information for 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.
This section contains the following topics:
Defining VLAN Properties
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Defining VLAN Membership
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Defining VLAN Interface Settings
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VLAN
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