Keep in mind I wrote router code in the 90s so to me this is not routing but Network Address Translation which is something entirely different from routing. So short answers only.
1. Yes.
2. Forget the idea of router to router. A router that does NAT doesn't care if the next device is a router or such. To the NAT software you have connections, etc. And yes, all frames bite?
3. For the internet the WAN are those IP addresses that are routeable. Our LAN are usually non-routeable addresses which is why NAT was invented.
Hello everybody, I am studying for CCNA exam and i kinda stuck into topic of routing, everything is clear for me, but when it comes to routing between router, i cannot build whole picture of how it happens:
1. Is MAC of interfaces between routers used during routing processes?
2. I am striving to understand how does the packet pass from one router to another on Layer 1 and 2 of OSI model?
Is there there encapsulation of packet into frame, and transformation of the frames into bites?
3. I have pretty clear image of how all this work inside Local network, but how all this works on WAN?
I am looking forward for some help!

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