Syntax ARP -s inet_addr eth_adr [if_addr]
ARP -d inet_addr [if_addr]
ARP -a [inet_addr] [-N if_addr]
| -a | Displays current ARP entries by interrogating the current protocol data. If inet_addr is specified, the IP and Physical addresses for only the specified computer are displayed. If more than one network interface uses ARP, entries for each ARP table are displayed. |
| -g | Same as -a |
| inet_addr | Specifies an Internet address. |
| -N if addr | Displays the ARP entries for the network interface specified by if_addr. |
| -d | Deletes the host specified by inet_addr. |
| -s | Adds the host and associates the Internet address inet_addr with the Physical address eth_addr. The Physical address is given as 6 hexadecimal bytes seperated by hyphens. The entry is permanent. |
| eth_addr | Specifies a physical address |
| if_addr | If present, this specifies the Internet address of the interface whose address translation table should be modified. If not present, the first applicable interface will be used. |
Examples arp -a Interface 220.0.0.80
| Internet Address | Physical Address | Type |
| 220.0.0.160 | 00-50-04-62-F7-23 | static |
The Physical Address or MAC address as shown above in the format aa-bb-cc-dd-ee-ff is the unique manufacturer identification number. This number should always be a unique address. An example of how to change the above IP address 220.0.0.160 to 220.0.0.161 in this case would be: arp -s 220.0.0.161 00-50-04-62-F7-23 If an IP address has already been assigned to the specific network adapter it is not possible to change that assigned IP address to a new address. In addition, networks italicizing DHCP, BOOTP or RARP will automatically assign the card an IP address, therefore, this command would not be utilized. | 
