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I have the following 3 devices on my network(a bus topology): A,B,C

Let

MAC(i) - denote the MAC address of the device i.
IP(i) - denote the IP address of the device i.

The devices B and C happen to have the following configuration:
MAC(B) == MAC(C) [I know it's very rare, but lets say B spoofed C's MAC]
IP(B) != IP(C)

A(has different mac and ip address from B,C) sends out a frame with
Destination MAC address = MAC(B) [which is == MAC(C)]
Destination IP address = IP(C)

Will C recieve the frame or will it be ambiguous? A nice explanation would be highly appreciated.

closed as off-topic by Ron Trunk, Teun Vink Sep 3 '17 at 16:55

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "NE is a site for to ask and provide answers about professionally managed networks in a business environment. Your question falls outside the areas our community decided are on topic. Please visit the help center for more details. If you disagree with this closure, please ask on Network Engineering Meta." – Ron Trunk, Teun Vink
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  • Smells like homework. What do you think will happen? – Ron Trunk Sep 3 '17 at 14:58
  • I think may be that the frame will be stripped off using MAC address at the data link layer, both at B and C. But the network layer at B would reject the frame, because it doesn't match the IP address. Not exactly homework, it was in my exam and I wish to know the solution : ) – packetChor Sep 3 '17 at 15:02
  • Exam questions are explicitly off topic here. Instead of thinking about what layers do, think about what individual hosts do. – Ron Trunk Sep 3 '17 at 15:46
  • @RonTrunk i discussed it with my peers and searched the internet for it, but Nowadays no one actually uses OSI, so I thought of asking it here. – packetChor Sep 3 '17 at 15:48
  • Layers don't do anything. They're just a mental model. Ethernet and IP are real protocols that have specific responses. Concentrate on that. – Ron Trunk Sep 3 '17 at 21:48
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It depends on what is connecting the devices.

If it is a hub then the frame will be delivered to both B and C.

If it is a switch then the frame will be delivered to whichever of B or C most recently sent a frame to the switch.

If the frame arrives at C it will be processed normally.

If the frame arrives at B then asuming B is configured an end node it will probably drop it. If B is configured as a router then it may try to route the packet. This may end up with a duplicate packet arriving at C.

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