Dimension ES-2008 Ethernet Switch

Chapter 9

VLAN

This chapter shows you how to set up Virtual LANs on the switch.

9.1Introduction

A Virtual LAN (VLAN) is a logical network grouping that limits the broadcast domain. It allows you to isolate network traffic so only members of the VLAN group receive traffic from the same VLAN group members. Members on a different VLAN group cannot communicate with each other even though they are physically connected to the same switch.

Your switch supports port-based and tag-based VLANs.

By default, all ports belong to a default VLAN (VLAN ID 1). You
cannot delete the default VLAN.

9.2VLAN Types

The following sections discussed the types of VLANs your switch supports.

9.2.1 Port-Based VLAN

Port-based VLAN is the most common and simplest form of VLAN. In a port-based VLAN, some ports are assigned to a VLAN group. A port can only belong to one VLAN group.

By default, all the ports on the switch belong to a VLAN group (VID 1). You cannot delete the default VLAN.

9.2.2 Tag-Based VLANs (IEEE 802.1Q VLAN)

Tag-based VLAN on the switch is based on the IEEE 802.1Q specification that allows you to create VLANs across switches from different vendors. IEEE 802.1Q VLAN inserts a “tag” into the Ethernet frames. The tag contains a VLAN Identifier (VID) that indicates the VLAN numbers.

The following lists the advantages of IEEE 802.1Q.

1.Multicast data traffic across different Ethernet devices is contained, thus improving performance.

2.A port can belong to more than one IEEE 802.1Q VLAN.

3.Improved security with logical grouping of users.

VLAN

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