Assuming you have the following network structure.


Knowing the IP address of the WWW-Server, system A wants to send an IP packet. As I understand the destination MAC address has to be in the same system, so it should be MAC-R1-1 in this case. But how does system A find out this specific MAC address? I know it will send out an ARP request containing the IP-WWW and the switch will flood the local network with the given IP address. But how will R1 answer with its MAC address if the IP address in the ARP request ist IP-WWW rather than IP-R1-1?

  • There are a lot of questions and answers about this here. – Ron Maupin Mar 10 '19 at 20:59
  • People are too lazy to do their own homework. – Ricky Beam Mar 10 '19 at 22:58

System A does not use ARP for the WWW server MAC address. It compares the destination IP address with its own network, and then it knows that the WWW server is on a different network, so it uses ARP to find the MAC address of its configured gateway, and it uses that to build the frame.

Not the answer you're looking for? Browse other questions tagged or ask your own question.