In this section, we are going to start learning about routing. 2
In the simple word, routing is communication between computer in the different block subnet. 3
For example, let’s import a router, as always, I use 2811, let’s also import 2 pc, 4
and then connecting this two pc to the router. 5
Remember that router is used to connecting many pc in the different block subnet, 6
so this 2 pc must be in the different block subnet. 7
Let’s say here we will configure 192.168.1.0/24 and then here 192.168.2.0/24. 8
Let’s change the name of the pc, this is pc 2, and this is pc 1. 9
Let’s configure the ip the ip address of the pc, start from pc 1, 10
desktop, ip configuration, the ip address is 192.168.1.10, 11
Remember that if computer want to communicate with others computer in the different block subnet, 12
so the computer will need a gateway, in this case the gateway will be the ip address of router, 13
let’s say the ip address of router will be 192.168.1.1, 14
and then the ip address that connected to pc 2 is 192.168.2.1, 15
So for pc 1, the gateway will be 192.168.1.1, and the gateway for pc 2 will be 192.168.2.1 16
Here for pc 1, the gateway is 192.168.1.1. Next for pc 2, 17
the ip address is 192.168.2.10, and the gateway is 192.168.2.1. 18
Next, let’s configure the ip address on the router. 19
No, enable, configure terminal, interface fa0/0, no shutdown to enable the interface, 20
okay now the light is green, then ip address 192.168.1.1 255.255.255.0, okay we have done for fa0/0. 21
Next for fa0/1, int fa0/1, no shutdown, the ip address is 192.168.2.1 255.255.255.0, 22
Okay now we have done configuring the ip address in the router, 23
Now pc 1 and pc 2 should be able to communicate. Let’s try, ping to pc 2, 192.168.2.10, 24
okay here we can see that the result is success. 25
So this is routing, which is communication between pc 26
in the different block subnet or different network. 27
How routing work? When pc 1 want to send packet to pc 2, pc 1 will ask the gateway or the router, 28
"hey router, do you know where is 192.168.2.10?" 29
When the router recieve a question like this, the router will check routing table, 30
To see the routing table, the command is do show ip route. 31
Here we can see that we have 2 entry in the routing table, which is 192.168.1.0/24 32
in fa0/0, and 192.168.2.0/24 in fa0/1. 33
Routing table is used to show which network are able to reach by the router. 34
In this case router are able to reach 192.168.1.0/24 which is connected to fa0/0, 35
and also able to reach 192.168.2.0/24 which is connected to fa0/1. 36
So when pc 1 ping to pc 2, pc 1 will ask the router where is 192.168.2.10, 37
the router know that 192.168.2.10 is in the fa0/1, so the packet will forwarded to fa0/1. 38
When the packet arrive in pc2, pc2 will send reply packet, 39
now the destination is 192.168.1.10 which is the ip address of pc 1. So pc 2 will ask the router, 40
"hey router, do you know where is 192.168.1.10?" the router will see the routing table, 41
and the router know that 192.168.1.10 is in the fa0/0, so the packet will be forwarded to fa0/0. 42
That is how routing work. 43
Okay I think enough for this video, in the next video, we are going to add 1 more router, 44
Thankyou for watching and see you on the next video.