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Resolved Question

Routing on WAN, how it happens? Do we need MAC?

Mar 12, 2016 10:30AM PST

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!

Discussion is locked

ConstantinCadin has chosen the best answer to their question. View answer

Best Answer

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Well that's not "routing."
Mar 12, 2016 10:41AM PST

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.

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usage of MAC on internet
Mar 12, 2016 10:48AM PST

2. In internet medium are MAC addresses used while traversing frame from one hop to another. This comes to me a bit confusing, can you clarify please!

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2. No.
Mar 12, 2016 10:57AM PST

For direct connections yes, but the IP address is what's used across the networks. There's a table that has the IP to MAC address in many devices so it can send the packet direct but the IP is in that packet. This is on the web so again I stop here.