How to Configure OSPF Routing on a Cisco Router using Cisco Packet Tracer

Packet Tracer is a program developed by Cisco to configure computer networks in a “virtual” way. This way, you can design a TCP/IP network in a virtual environment with this software before ensuring it will work in a real scenario.

An OSPF network can be divided into smaller regions (areas). A particular area called the backbone area forms the central portion of the network to which the rest of the network is connected. The paths between different areas constantly circulate in the spine, so all areas must be connected to the spine. A virtual connection between networks can be made if a link to the backbone cannot be established.

Routers in the same multicast domain or at the end of a point-to-point connection form create connections when they discover each other. In the Ethernet network segment, the routers select a designated router (Dedicated Router, DR) and a fixed secondary or replica router (Redundant Dedicated Router, BDR) that serve as hubs to reduce traffic between different routers.

OSPF can use multicast and unicast to send welcome packets and link status updates. The multicast addresses used are and Unlike RIP or BGP, OSPF does not use TCP or UDP. Instead, it encapsulates directly on the IP protocol by placing “89” in the protocol field.

OSPF regulates an autonomous system (AS) in areas. These fields are groups of logical routers whose information can be summarized for the rest of the network.

A domain is a routing unit, meaning all routers in the same domain hold the same topology map information in the Connection State Databases.

How to Enable OSPF on Cisco Router

This article will enable the OSPF routing protocol on a Router with Cisco’s Packet Tracer software.

To set up the OSPF protocol:

Step 1: If you have not previously installed Packet Tracer on your computer, check the following articles to install it on Windows, Linux, and macOS.

Step 2: After installation, open the simulator program and add two Cisco Routers to the workspace.

Step 3: Click on them to add Serial Interface to the Routers you have added and add the HWIC-2T module on the left side of the window.

Step 4: Add two Cisco Switches to the network topology and connect them to the routers.

Step 5: To connect between routers, select Serial cable from the cable types and click on them to join the line to the free ports.

Step 6: Add four PCs to the network topology and configure TCP/IP settings.

Step 7: Specify an IP block for the network between routers. Then, create two segments by specifying an IP block for the subnets of the Routers connected to the GigabitEthernet interfaces.

Step 8: After designing the network’s IP, run the following commands on R1 and R2 to activate OSPF Routing on the Router.

R1# conf t
R1(config)# router ospf 10
R1(config-router)# network area 0
R1(config-router)# network area 0
R1(config-router)# end

R2# conf t
R2(config)# router ospf 10
R2(config-router)# network area 0
R2(config-router)# network area 0
R2(config-router)# end

Step 9: Test the network connection between all network devices after configuring OSPF Protocol on the Routers with the Cisco simulator software.

   Related Articles

1. What is RIP
2. Cisco VLAN

In other languages: TR
Avatar for tolgabagci


In my personal blog, I will explain the solutions to the problems I encounter in the system, network, and information technologies for you. If you want to contact me or consult about a problem, you can send an e-mail to