User manual

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ES-2000 Series
6 VLAN CONFIGURATION
IEEE 802.1Q VLANS
In large networks, routers are used to isolate broadcast traffic for each
subnet into separate domains. This switch provides a similar service at
Layer 2 by using VLANs to organize any group of network nodes into
separate broadcast domains. VLANs confine broadcast traffic to the
originating group, and can eliminate broadcast storms in large networks.
This also provides a more secure and cleaner network environment.
An IEEE 802.1Q VLAN is a group of ports that can be located anywhere in
the network, but communicate as though they belong to the same physical
segment.
VLANs help to simplify network management by allowing you to move
devices to a new VLAN without having to change any physical connections.
VLANs can be easily organized to reflect departmental groups (such as
Marketing or R&D), usage groups (such as e-mail), or multicast groups
(used for multimedia applications such as video conferencing).
VLANs provide greater network efficiency by reducing broadcast traffic, and
allow you to make network changes without having to update IP addresses
or IP subnets. VLANs inherently provide a high level of network security
since traffic must pass through a configured Layer 3 link to reach a
different VLAN.
This switch supports the following VLAN features:
◆ Up to 128 VLANs based on the IEEE 802.1Q standard
◆ Distributed VLAN learning across multiple switches using explicit or
implicit tagging
◆ Port overlapping, allowing a port to participate in multiple VLANs
◆ End stations can belong to multiple VLANs
◆ Passing traffic between VLAN-aware and VLAN-unaware devices
◆ Priority tagging
Assigning Ports to VLANs
Before enabling VLANs for the switch, you must first assign each port to
the VLAN group(s) in which it will participate. By default all ports are
assigned to VLAN 1 as untagged ports. Add a port as a tagged port if you
want it to carry traffic for one or more VLANs, and any intermediate