Moxa EDS-82810G [54/113] What is a vlan

EDS-828 Series Featured Functions

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Using Virtual LAN

Setting up Virtual LANs (VLANs) on your EDS-828 increases the efficiency of your network by dividing the LAN

into logical segments, as opposed to physical segments. In general, VLANs are easier to manage.

The Virtual LAN (VLAN) Concept

What is a VLAN?

A VLAN is a group of devices that can be located anywhere on a network, but which communicate as if they are

on the same physical segment. With VLANs, you can segment your network without being restricted by physical

connections—a limitation of traditional network design. As an example, with VLANs you can segment your

network according to:

• Departmental groups—You could have one VLAN for the Marketing department, another for the Finance

department, and another for the Development department.

• Hierarchical groups—You could have one VLAN for directors, another for managers, and another for

general staff.

• 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:

• 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 carry out any re-cabling.

• 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.

• 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.