User`s manual

EDS-405A/408A Series User’s Manual Featured Functions
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y Hierarchical groups—You could have one VLAN for directors, another for managers, and
another for general staff.
y Usage groups—You could have one VLAN for e-mail users, and another for multimedia
users.
Benefits of VLANs
The main benefit of VLANs is that they provide a network segmentation system that is far more
flexible than traditional networks. Using VLANs also provides you with three other benefits:
y VLANs ease the relocation 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 host must be updated manually. With a VLAN
setup, if a host on 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 on VLAN Marketing. You do not need to do any re-cabling.
y VLANs provide extra security: Devices within each VLAN can only communicate with
other devices on the same VLAN. If a device on VLAN Marketing needs to communicate
with devices on VLAN Finance, the traffic must pass through a routing device or Layer 3
switch.
y VLANs help control traffic: With traditional networks, congestion can be caused by
broadcast traffic that is directed to all network devices, regardless of whether or not they need
it. VLANs increase the efficiency of your network because each VLAN can be set up to
contain only those devices that need to communicate with each other.
VLANs and Moxa EtherDevice Switch
Your EDS provides support for VLANs using IEEE Std 802.1Q-1998. This standard allows traffic
from multiple VLANs to be carried across one physical link. The IEEE Std 802.1Q-1998 standard
allows each port on your EDS to be placed in:
y Any one VLAN defined on the EDS.
y Several VLANs at the same time using 802.1Q tagging.
The standard requires that you define the 802.1Q VLAN ID for each VLAN on your EDS before
the switch can use it to forward traffic:
1
2
3
4
5
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1
2
3
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Switch A
Switch B
Backbone connects multiple switches
Department 1
VLAN 1
Department 2
VLAN 2
Department 3
VLAN 3