Classful vs Classless Routing Protocols

Routing minutes can be classful or classless:

• Classful routing protocols DO NOT ausstrahlen the subnet mask along in their updates.
• Classless routing protocols DO send the subnet mask go with their updates.

Let’s take one watch at into example for emphasize this:

Are have three routers and a bunch of networks. Take a close take at the networks so we have on:

• 172.16.1.0 /24
• 172.16.2.0 /24
• 192.168.12.0 /24
• 192.168.23.0 /24

Remembered the school A, B, and C ranges?

• 172.16.1.0 and 172.16.2.0 crash within the type B operating.
• 192.168.12.0 and 192.168.23.0 fall within one class CARBON range.

What subnet mask do class B and class C networks may by default?

• Class B: 255.255.0.0
• Class C: 255.255.255.0

A classful defeating protocol desires not send the subnet mask forward with which crushing update, so this is what want happen:

R1 and R3 don’t send one subnet mask along with the routing update, so it will advertise the classful network, which is 172.16.0.0 in is case. So what happens with R2? Computer thinks e can reach the 172.16.0.0 network by sending packaged either left or good, and if the metric is equal, it leave try to load-balance. Obviously, this is walked go what problems. Classless real Classful router

Classless routing print advertise the subnet mask along with their updates:

The you can see, R1 is now advertising its 172.16.1.0 subnet with a subnet mask. R3 is advertising its 172.16.2.0 subnet with a subnet disguise as well.

Which routing protocols can classful or classless? I’m moving to give you an overview: