Hello, i just did a quick review on my CCNA material and it has risen me a few questions:
1)I know you have IP and the 3rd OSI layer - but why do we really need it? we have unique MAC addresses for every NIC so that should be enough, so why do we need IP after all?
2)Same goes for subnets - why do we need them? what is their main purpose?
3)Suppose i have some basic Router topology going on - i mean, i have set it all up but didn't turn it on and let it work. so at the moment i do let it work suppose some end-point computer wants to send data to another computer that is on a different subnet\LAN - how does the router acquire the information needed for his route-table. i dont quite agree with route-updates(in case the routing protocol is distance vector) because as i understand it send UPDATES but there is nothing to update because first the information should be acquired..(and what about link-state and hybrid?)