ARP: Displaying Physical Addresses Remember that to send a message to other computers on the Internet, you must know the physical address (aka data link layer address) of the next computer to send the message to. Most computers on the Intenet will be outside your subnet, so almost all messages your computer sends will be sent to your gateway (i.e., the router leaving your subnet). Remember that computers use ARP requests to find physical addresses and store them in their ARP tables. To find out what data link layer addresses your computer knows, you can use the ARP command. At the command prompt, type ARP-A and press enter. This will display the contents of your ARP table. In Figure 5-23, you can see that the ARP table in my computer has only one entry, which means that all the messages from my computer since I tuned it on have only gone to this one computer-my router. You can also see the physical address of my router: 00-04-5a-0b-d1-40 C1Dacunents and Settingedninistratorsarp.-a Intertace: 192.168.1.102x10003 Internet Addres8 192.168.1.1 Phyeical Aadre99 00-04-5a-0b-il-40 dynamic Type C:Docunents and SettingstAainistratorping 192.168.1.152 Pinging 192.168.1.152 with 32 bytes of datai Reply fron 192.168.1.152: bytes32 time 1ma TTL -64 Reply fron 192.168.1.152 bytes 32 time