Every node in a cluster, is appointed an IP Address

and under the node, a private IP address is set to communicate between pods.

Here 10.244.0.0 is a private network which pods use.

If there are multiple nodes in a cluster, surely the nodes have different IP addresses.

But the problem is with the private network created to connect the nodes.

That is same to all the nodes.

So, you can see the internal network address is same for all. This makes a conflict if we want to contact with pods outside of a node.

Thus there are some external third party tools, we have to use.

After using the third party tools, they appoint a different internal network for different node's pods. Thus it is now easy to communicate to different pods.

That was it for the basics. We made it simple for you boss!