CISCO ROUTING INFORMATION PROTOCOL (RIP)
The Routing Information Protocol (RIP) is one of the oldest distance-vector routing protocols which employs the hop count as a routing metric. RIP prevents routing loops by implementing a limit on the number of hops allowed in a path from source to destination. Now we will apply and practice Cisco RIP by example.
Exercise 1
See the picture above, first please define the IP Address on Router 1, Router 2, and Router 3. Follow the command below,
hostname R1
int e0/0
ip addr 13.1.1.1 255.255.255.0
no shutdown
int e0/1
ip addr 12.1.1.1 255.255.255.0
no shutdown
int lo 0
ip addr 13.1.1.1 255.255.255.0
ip addr 1.1.1.1 255.255.255.0
no shutdown
do write
do show ip int brief
hostname R2
int e0/0
ip addr 23.1.1.2 255.255.255.0
no shutdown
int e0/1
ip addr 12.1.1.2 255.255.255.0
no shutdown
int lo 0
ip addr 2.2.2.2 255.255.255.0
no shutdown
do write
do show ip int brief
hostname R3
int e0/0
ip addr 13.1.1.3 255.255.255.0
no shutdown
int e0/1
ip addr 23.1.1.3 255.255.255.0
no shutdown
int lo 0
ip addr 3.3.3.3 255.255.255.0
no shutdown
do write
do show ip int brief
To make sure the IP Address is correctly, you can check by command
do show ip int brief, see the picture belowNow, you can try to ping from each Router before setting the Router Rip step, See the figure below,
And also you can try to ping the loopback, try the command below
ping 1.1.1.1 source 2.2.2.2
ping 1.1.1.1 repeat 10 source 23.1.1.2
ping 1.1.1.1 repeat 10 source 2.2.2.2
You can see the result by the following picture,
Now you can add the Router RIP to every Router, run the command below,
hostname R1
router rip
version 2
no auto-summary
network 13.1.1.0
network 12.1.1.0
network 1.1.1.0
exit
do show run
show ip route rip
hostname R2
router rip
version 2
no auto-summary
network 12.1.1.0
network 23.1.1.0
network 2.2.2.0
exit
do show run
show ip route rip
hostname R3
router rip
version 2
no auto-summary
network 13.1.1.0
network 23.1.1.0
network 3.3.3.0
exit
do show run
show ip route rip
See the picture below, you can use the open-source packet analyzer, to see more clearly how Router RIP works,
While, Loopback is virtual interfaces in cisco router, now you can add more loopback, we will try at Router 3, run command below,
int lo 1
ip addr 172.16.0.1 255.255.255.0
no shutdown
int lo 2
ip addr 172.16.1.1 255.255.255.0
no shutdown
int lo 3
ip addr 172.16.2.1 255.255.255.0
no shutdown
int lo 4
ip addr 172.16.3.1 255.255.255.0
no shutdown
do sh ip int brief
router rip
network 172.16.0.0
do show run
ctrl +Z
show ip route
You can see the result by the following picture,
Router RIP - Passive Interface
Passive Interface will ensure that the network is advertised in RIP but it will not send RIP updates on the interface. You can see the picture above, In this case to apply the passive interface is when the R3 just want to execute 172.0.23.0/24, but not 172.0.34.0/24. So now, please define the ip address on Router 1, Router 2 and Router 3, and do the same things for router rip command, and after that you can apply the passive interface, there are two methods that you can apply,
First method is using network 172.0.0.0 will make both interface become RIP， so one must be added command to prevent e0/1 from performing RIP,
-
Second method is make all interface passive, and then no interface will be executed, run command,passive-interface
passive-interface default
on passive-interface e0/0
Router RIP - Default Information Originate
To generate a default route into the Routing Information Protocol (RIP), use the default-information originate command. Now, R2 wants to release default route to R1 and R3, so we just use following command,
router rip
default-information originate