3Com 3C17203 - SuperStack 3 Switch 4400, Руководство по внедрению

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Figure 18 A network setup showing three VLANs
Benefits of VLANs
The main benefit of VLANs is that they provide a network segmentation
system that is far more flexible than any traditional network. Using VLANs
also provides you with three other benefits:
■
VLANs ease the movement of devices on networks
With traditional networks, network administrators spend much of
their time dealing with moves and changes. If users move to a
different subnetwork, the addresses of each endstation must be
updated manually.
With a VLAN setup, if an endstation in VLAN Marketing for example is
moved to a port in another part of the network, and retains its original
subnet membership, you only need to specify that the new port is in
VLAN
Marketing . You do not need to carry out any re-cabling.
■
VLANs provide extra security
Devices within each VLAN can only communicate with other devices in
the same VLAN. If a device in VLAN
Marketing needs to communicate
with devices in VLAN Finance , the traffic must pass through a routing
device or Layer 3 Switch.
VLAN 1
VLAN 3
VLAN 2
Marketing Department
Development Department
Finance Department
Switch A Switch B
Backbone connecting multiple switches
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2
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