How to Find an ARP

Address Resolution Protocols, or ARPs, are network protocols which help network devices such as computers transmit data packets across local area networks. Before a computer or other network-device transmits to another device on its local area network, it uses ARP to identify the physical address of the device it is trying to communicate with. This enables devices to properly address packets to ensure receipt by the destination device. Computers briefly store (cache) ARP entries in their memory in what is known as an ARP table.

Instructions

1

Open the MS-DOS command prompt window. From the "Start" menu in Windows 7, Windows Vista or Windows XP, select 'Run' and then type "cmd" and click "OK." (In earlier versions of Windows, type "command" and press enter.)

2

Display the ARP table by typing "arp -a" in the command prompt window and pressing "Enter." This command will display all current devices cached in your computer's ARP table, whether statically or dynamically assigned.

3

Add or remove entries from the ARP table by entering the appropriate command. Typing "arp" and pressing "Enter" will reveal a list of appropriate arguments for the "arp" command. For example, the sample ARP entry command "arp -s 192.168.1.111 00:11:22:33:44:55" would tell your computer that the physical device 00:11:22:33:44:55 was located at the current network address of 192.168.1.111.