VLAN

A virtual LAN (VLAN) is any broadcast domain that is partitioned and isolated in a computer network at the data link layer (OSI layer 2). LAN is an abbreviation of local area network. To subdivide a network into virtual LANs,one configures a network switch or router.

• A Vlan is a logical partition of a layer 2 Network
• Multipal partition can be created
• Each Vlan is a broadcast domain,with own ip address

Benefits Of Vlan

• Security
• Cost Reduction
• Better performance
• Shrink boroadcast domains

Types Of Vlan

• Data Vlan
• Default Vlan
• Native Vlan
• Management Vlan

Coding

switch#show Vlan brief

Creating a Vlan

S1#Config T

S1(Config)#Vlan 10

S1(Config)#Name Student

S1(Config)#end

Assigning Ports to Vlan

S1#Config T

S1(Config)#interface fas0/1

S1(Config)#ip address()

S1(Config)#switchport mode acess

S1(Config)#switchport acess vlan 10

S1(Config)#exit

Changing Vlan Port Membership

S1#Config T

S1(Config)#int fa0/1

S1(Config)#switchport mode acess

S1(Config)#switchport acess vlan 10

S1(Config)#exit

Deleting Vlan

S1(Config)#no vlan 10

S1(Config)#exit

Verfying vlan information

S1#show vlan name student

Activity (Inter-Vlan Routing)

Vlan 20=192.168.20.1

Vlan 30=192.168.30.1

Switch

S1(Config)#Vlan 20

S1(Config)#Name IT

S1(Config)#Vlan 30

S1(Config)#Name ART

S1(Config)#int fa0/1

S1(Config-if)#switchport mode Trunk

S1(Config)#int range fa0/2-3

S1(Config)#switchport acess vlan 20

S1(Config)#int range fa0/4-5

S1(Config)#switchport acess vlan 30

Router

R1(Config)#int fa 0/0

R1(Config-if)#no ip address

R1(Config)#int fa 0/0.20

R1(Config)#encapsulation do1Q 20

R1(Config)#ip address 192.168.20.1 255.255.255.0

R1(Config)#int fa 0/0.30

R1(Config)#encapsulation do1Q 20

R1(Config)#ip address 192.168.30.1 255.255.255.0

R1(Config)#int fa 0/0
R1(Config-if)#no shutdown