How To Configure The Cisco Router

There are 4 rules to assign IP addresses to the routers.

  1. All the interfaces of routers should be in a different network (subnet).
  2. Both interfaces of routers facing each other should be in the same network (subnet).
  3. LAN  that under the router interface should be n the same network (subnet).
  4. All the LAN and WAN networks must be in a different network (subnet)

Configure interfaces of routers should be in the interface mode which under the global configuration mode.

  • Router>enable
  • Router#configure terminal
  • Router(config)#İnterface <interface type> <interface no>  İnterface mode is entered
  • Router(config-if)#ip address <ip no> <subnet musk no>  Assigning ip address
  • Router(config-if)#no shutdown  Opens the inerface that closees by default.
  • Router(config-if)#clock rate 64000   just for lab scenario not for the real world.

Let’s configure the example with 3 routers given below with the above commands

router topology

router topology

Router configuration R1

Router configuration R2

Router configuration R3

To verify the state of the interfaces that configured above we should use show IP interface brief command on the privileged mode.  This command shows us brief knowledge regarding interfaces.

Now we learned how to configure router interfaces. However, just with this configuration, computers under Routers can communicate with each other, while they cannot communicate with computers under different routers.  Why? Because routing protocols are needed for communication between different networks. Computers on the same network do not need routing protocols because they communicate with their mac addresses. Routing protocols enable routers to recognize different networks. Thus, we have completed the router configuration in this article.

In the next article, we will cover the types of router protocols and how to configure them.

I hope it was a useful article.