vlan basics

This tutorial understands the basics of vlan, it’s use on a network and the different concepts associated with it.

This content is a preview from the book -VLAN NETWORK DESIGN

Vlans are used for segregating networks and for broadcast controls. It is predominantly used for setting up of networks which has multiple subnets. VLAN technology is supported in switches and routers. Ports on switches can either be a member of specific vlan or multiple vlans. In a Cisco switch, port based vlans are used to assign a port as a member of a specific vlan. Trunk links are used when ports are required to carry multiple vlans.

VLAN’s are typically created based on the number of networks. For ex, if a network has three departments like Finance , IT, and HR, three nos of vlans would be required, for each of the networks. The vlans are mapped with the respective network address of the departments. The vlan tables along with the network address for the departments are shown below.

VLAN BASICS

Switch configuration to make port as vlan members.

The details of configuration to be performed on a Cisco switch for creating vlan 2 and making port 4 as member of vlan 2 is shown

1.Create the necessary vlan on the switch

switch(config)#vlan 2

2.Configure the port as member of vlan 2. (Port 4)

Switch(config)#interface fastethernet 0/4
Switch(config-if)#switchport mode access
Switch(config-if)#switchport access vlan 2

This step is followed for making ports members of the respective vlans.

The above content is a preview from the book – VLAN NETWORK DESIGN