Enterasys Networks 2200 - Manual (Page 264)

Defining VLANs
12-2 VLAN Operation and Network Applications
The creation of VLANs allows users located in separate areas or connected to separate ports to
belong to a single VLAN group. Users that are assigned to such a group will send and receive
broadcast and multicast traffic as though they were all connected to a common network.
VLAN-aware switches isolate broadcast, multicast, and unknown traffic received from VLAN
groups, so that traffic from stations in a VLAN are confined to that VLAN.
When stations are assigned to a VLAN, the performance of their network connection is not
changed. Stations connected to switched ports do not sacrifice the performance of the dedicated
switched link to participate in the VLAN. As a VLAN is not a physical location, but a
membership, the network switches determine VLAN membership by associating a VLAN with a
particular port or frame type.
Figure 12-1 shows a simple example of a port based VLAN. Two buildings house the Sales and
Finance departments of a single company, and each building has its own internal network. The
stations in each building connect to a SmartSwitch in the basement. The two SmartSwitches are
connected to one another with a high speed link.
Figure 12-1 Example of a VLAN
1
S S
F
F
A 6
S S S
F F
B 7
8
9
10
Building One Building Two
SmartSwitch SmartSwitch
trunk
30691_58
Member of Sales Network Member of Finance Network
S
S
F