What is Address Resolution Protocol (ARP)
Address Resolution Protocol (ARP) enables a TCP/IP computer to convert IP addresses to the hardware addresses that data-link layer protocols need to transmit frames across local subnets. IP uses ARP to discover the hardware address to which each of its datagrams will be transmitted. To minimize the amount of network traffic ARP generates, the computer stores the resolved hardware addresses in a cache in system memory. The information remains in the cache for a short time (usually between 2 and 10 minutes), in case the computer has additional packets to send to the same address.
You can use Arp.exe to add the hardware addresses of computers you contact frequently to the cache, saving time and reducing network traffic during the connection process. Addresses that you add to the ARP cache manually are static, meaning that they are not deleted after the usual expiration period.
The cache is stored in memory only, however, so it is erased when you reboot the computer. If you want to preload the cache whenever you boot your system, you can create a script containing Arp.exe commands and execute it by placing it in the Startup program group (in Windows).
The Arp.exe syntax and command-line arguments are as follows:
Examples
To display the ARP cache tables for all interfaces, type:
To display the ARP cache table for the interface that is assigned the IP address 10.0.0.99, type:
To add a static ARP cache entry that resolves the IP address 10.0.0.80 to the physical address 00-AA-00-4F-2A-9C, type:
You can use Arp.exe to add the hardware addresses of computers you contact frequently to the cache, saving time and reducing network traffic during the connection process. Addresses that you add to the ARP cache manually are static, meaning that they are not deleted after the usual expiration period.
The cache is stored in memory only, however, so it is erased when you reboot the computer. If you want to preload the cache whenever you boot your system, you can create a script containing Arp.exe commands and execute it by placing it in the Startup program group (in Windows).
The Arp.exe syntax and command-line arguments are as follows:
Examples
To display the ARP cache tables for all interfaces, type:
Code:
arp -aTo display the ARP cache table for the interface that is assigned the IP address 10.0.0.99, type:
Code:
arp -a -N 10.0.0.99To add a static ARP cache entry that resolves the IP address 10.0.0.80 to the physical address 00-AA-00-4F-2A-9C, type:
Code:
arp -s 10.0.0.80 00-AA-00-4F-2A-9C