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MAC-address for Cisco

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So I'm trying to ping Cisco to get the MAC-address. In the Destination section I get OpenWrt.lan and a MAC-address, but in the video below it shows Ciscospv_cd instead of OpenWrt.lan. Am I doing something wrong here? The same thing happened when I tried to ping Yahoo.

https://www.youtube.com/watch?v=xVwFjH0sQUI

asked 11 Oct '17, 08:30

captainpancake133's gravatar image

captainpanca...
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One Answer:

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You are about 16 minutes into this video and are asked to ping yahoo.com and cisco.com. The next question is 'what is significant about this information' and the answer is 'All MAC addresses are the same'. Now why is that? That comes from the fact that yahoo.com and cisco.com are resolving to IP addresses outside of your local network. Therefore all this ICMP packets go to your router first, and therefore it's the router MAC address you'll see.

In the presenters case, he has some Cisco device as his router, therefore sees the manufacturer name Ciscospv_cd in the MAC address, while you have a LinkSys router of some kind, therefore you see the OpenWrt.lan name.

So in short, he doesn't see the cisco.com MAC address, he sees the MAC address of his router, which happens to be a Cisco device.

answered 11 Oct '17, 10:04

Jaap's gravatar image

Jaap ♦
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Got it. So in short: Pinging local IP addresses will give you the MAC-address, but pinging remote hosts won't. Am I correct on that?

(11 Oct '17, 10:23) captainpanca...

Pinging local IP addresses will give you the MAC-address, but pinging remote hosts won't.

Correct, with "local" meaning "on the same LAN". If you're on a network segment that uses MAC addresses, pinging an IP address will give you the MAC address of the first host on the route to that IP address, which would be the host with that IP address if they're on the same network segment and would be a router if they're not on the same network segment.

(11 Oct '17, 11:27) Guy Harris ♦♦