Free The data link layer lessonsThe data link layer · Stage 2 · Sharing the wire · Step 2
ARP and how switches learn
Find the MAC address that goes with an IP address, and see how a switch builds its table from the frames it sees. About 13 minutes.
Host A wants to send to a server on a different network. Whose MAC address does A use as the frame's destination?
- AThe default gateway's (the router's)
- BThe server's, found by ARP across the Internet
- CThe broadcast address
Show the answer
The default gateway's (the router's). The frame has to reach the router; the packet inside still carries the server's IP address.
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