As a network administrator, tasks may encompass having to segment a single switched neighborhood Area Network (LAN) logically without having to run new cables and transforming the existing network. The ide of “VLAN” and its configurations will help one handle the task at hand with ease.

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In this article, we will certainly learn around what inter-VLAN routing is, various approaches for VLAN routing, and likewise build a network construction to understand just how it works.

Table that contents

Inter-VLAN routing methodsNetwork configurations for Inter-VLAN communication using Router-On-Stick method


As a prerequisite, the leader must have actually a an excellent understanding of straightforward networking concepts, and also how to work with Cisco packet tracer.

To download and install Cisco packet tracer on your computer, visit this link.

VLAN routing terminologies

VLAN is a network segment on a switched LAN which groups together the master on the network, logically, nevertheless of your physical places on the network.A local Area Network (LAN) is a physics interconnection that network devices in a little geographical area.Layer 3 switch/multilayer switch is a special kind of switch which performs the duty of both switches at layer 2 and routers in ~ layer 3 of the OSI model i.e., it deserve to forward both the frames and also packets.Switched Virtual user interface (SVI) refers to a virtual interface which connects VLANs top top the network tools to their corresponding router engines.Default Gateway is a device that forwards IP packets and provides an accessibility point to the other networks. For instance, a router.Access Point is a network maker that connects come a router or switch, developing a wireless regional area network and also acting as a link in between the router and also the network users.Switch port refers to a physical opening on the move or router where ethernet cables can be plugged.Router user interface refers come a route that enables the router to attach to the network.

What is Inter-VLAN routing?

Virtual LANs (VLANS) are networks segment on a switched LAN. Inter-VLAN routing refers to the movement of packets throughout the network in between hosts in different network segments.

VLANs do it easier for one come segment a network, i m sorry in turn improves the performance of the network and also makes it much more flexible, since they room logical connections.

VLANs act as different subnet on the network. To relocate packets indigenous one VLAN to one more and permit communications among hosts, we have to configure the VLAN network.

Inter-VLAN routing methods

Legacy inter-VLAN routing

In this method, many router interfaces are used, each connecting come a switch harbor in various VLANs. These interfaces are offered as default gateways, which requires extr cabling once the network has to be expanded.

Hence, including additional network cables and improving framework is more expensive.


In this method, unequal the tradition routing, one physical user interface port is offered for routing the traffic in between the network segments. The network administrator doesn’t need to produce separate VLAN interfaces prefer fa0/1 come fa0/10.

Instead, all the interfaces native 1 come 10 are developed with a solitary interface. This an approach is an easy to implement and also used for tiny to medium-sized networks.

Layer 3 switch using Switched Virtual user interface (SVI)

Currently, this an approach of inter-VLAN routing that offers layer 3/multilayer switch and Switched digital Interfaces (SVI) is the many preferred.

SVIs are developed for VLANs exist on the switch which performs the same role for the VLANs as that of a router.

Layer 3 switches space expensive, which room primarily perfect for huge organization networks.

Network configurations for Inter-VLAN communication using Router-On-Stick method

In this article, we will learn just how to configure inter-VLAN routing utilizing the router-on-a-stick method.

Consider a LAN v 4 PCs, 1 switch, and a router connected as displayed in the image:


Now, we need to configure 2 VLANs 10 and also 20, v PC0 and PC1 top top VLAN10, and also PC2 and PC3 space on VLAN20.

IP address of PC0 - deal with of PC1 - deal with of PC2 - attend to of PC3 - default gateway for VLAN10 - default gateway for VLAN20 - 1

For united state to subdivide the network right into two subnets, we have to create two VLANS top top the switch, VLAN10 and also VLAN20. Provide them practice names like VLAN 10 - student and also VLAN 20 - staff.

To produce two VLANs, we get in the configuration mode using the config terminal command, and also then we go into the VLAN number choose vlan 10 along with the name.

Switch>enable !moving native user exec setting to priviledge modeSwitch#config terminal !moving from priviledge setting to worldwide configuration modeSwitch(config)#vlan 10 !assigning vlan numberSwitch(config-vlan)#name student !assigns the vlan 10 the name studentSwitch(config-vlan)#exitSwitch(config)#vlan 20Switch(config-vlan)#name employee !assigns vlan 20 the name staffSwitch(config-vlan)#exit
Step 2Assign switch ports to the VLANS. Harbor fa0/1 and also fa0/2 exhilaration as accessibility ports for VLAN10, if ports fa0/3 andfa0/4 for VLAN20.

We shall usage fa0/5 harbor for the trunk harbor for carrying the traffic in between the 2 VLANS via the router.

NOTE: fa refers to rapid ethernet ports offered for connecting the network master to the move or router.

Configurations for accessibility ports fa0/1 and also fa0/2

Switch>enable !moving from user exec setting to the priviledge modeSwitch#config terminal !moving native priviledge mode to the worldwide configuration modeSwitch(config)#int fa 0/1 !entering the interface portSwitch(config-if)#switchport mode access !making the user interface fa0/1 an accessibility portSwitch(config-if)#switchport access vlan 10 !making interface accessibility port for vlan 10Switch(config-if)#exit !exiting from the interfaceSwitch(config)#int fa 0/2 !entering the user interface portSwitch(config-if)#switchport mode accessibility !making the user interface fa0/2 an accessibility portSwitch(config-if)#switchport access vlan 10 !making interface accessibility port for vlan 10Switch(config-if)#exit !exiting from the interface
In the construction above, fa0/1 and fa0/2 room configured as access ports making use of the command switchport setting access.

Since castle belong come vlan10, the switchport accessibility vlan 10 command is provided to configure castle as access ports within vlan10.

Configurations for accessibility ports fa0/3 and fa0/4

Switch(config)#int fa 0/3 !entering the interface portSwitch(config-if)#switchport mode accessibility !making the user interface fa0/3 an accessibility portSwitch(config-if)#switchport access vlan 20 !making interface access port because that vlan 10Switch(config-if)#exit !exiting indigenous the interfaceSwitch(config)#int fa 0/4 !entering the user interface portSwitch(config-if)#switchport mode accessibility !making the interface fa0/4 an access portSwitch(config-if)#switchport accessibility vlan 20 !making interface access port because that vlan 10Switch(config-if)#exit
In the configuration above, fa0/3 and also fa0/4 room configured as access ports making use of the command switchport mode access.

Since they belong to vlan20, the switchport access vlan 20 command is supplied to configure lock as access ports within vlan20.

Configurations for trunk harbor fa0/5

Switch(config)#int fa 0/5 !entering the user interface portSwitch(config-if)#switchport mode trunk !making interface a tribe port.Switch(config-if)#do create !saving the to run configurations to start-up file
From the above code interface, fa0/5 is serving as our stems port. To configure it to offer as a tribe port and also not an accessibility port, we usage the command switchport setting trunk in the worldwide interface mode.

Step 3

Using revolution IP addressing, collection the IP addresses to revolution on each computer on the network.


Step 4

Configure the router to allow the website traffic to relocate from VLAN10 to VLAN20. Because that the computers to communicate, us subdivide the solitary interface into many sub-interfaces, whereby each sub-interface will act as the default gateways because that each of the VLANs. This will allow two below networks to connect using the single interface.

Router>enable !moving from user exec mode to the priviledge exec modeRouter#config terminal !moving from priviledge exec mode to the worldwide configuration modeRouter(config)#int g0/0 !entering top top our physics router interface gigabitEthernet 0/0Router(config-if)#no shutdown !activating the interfaceRouter(config-if)#int g0/0.10 !first sub user interface for vlan 10 top top g0/0Router(config-subif)#encapsulation dot1q 10 !configuring the sub user interface to respond to website traffic from vlan 10Router(config-subif)#ip add !configuring the IP attend to of the sub interface g0/0.10Router(config-subif)#exit !exiting from the below interfaceRouter(config)#int g0/0 !entering our physics router interfaceRouter(config-if)#no shutdown !activating our physical interfaceRouter(config-if)#int g0/0.20 !second sub interface for vlan 20 on g0/0Router(config-subif)#encapsulation dot1q 20 !configuring the sub interface to answers to website traffic from vlan 20Router(config-subif)#ip include !configuring the IP address of the sub user interface g0/0.20Router(config-subif)#exitRouter(config)#do write !saving our to run configurations into the start-up construction fileRouter(config)#exit
From the construction above, the interface g0/0 is subdivided into two below interfaces: g0/0.10 because that VLAN10 and g0/0.20 for VLAN20.

Then, the two sub-interfaces room assigned IP addresses and also serve together the trunk harbor for carrying the traffic.

Step 5

Test the inter-VLAN connectivity by trying to ping the different PCs.

For instance, if we ping PC2 in VLAN20 indigenous PC0 in VLAN10, it need to be effective as presented below:



Inter-VLAN routing is an essential concept because that anyone who has the passion for networking. The is the practically and better way come subdivide a big LAN and also to permit communication between the network hosts.

You have the right to find an ext information around inter vlan routing here.

To summarize:

We learned what VLAN routing is.We explored various methods come route.We configured the course using route-with-stick method.

Happy coding.

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Peer review Contributions by: Srishilesh ns S

about the writer
Atonya Dennis

Atonya Dennis is a Computer modern technology student at Jomo Kenyatta college Of farming and Technology. His interests room web development and networking. Dennis has actually a great passion for occurring web applications and configuring networks.