Arp Configuration; Introduction To Arp; Arp Function; Arp Message Format - 3Com 4500 PWR 26-Port Configuration Manual

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ARP Configuration

Wh n configuring ARP e

Introduction to ARP

Configuring ARP
Configuring Gratuitous ARP
Displaying and Debugging ARP
ARP Configuration Ex
Introduction to ARP
ARP Function
Address Resolution Protocol (ARP) is used to resolve an IP address into a data link layer address.
An IP address is the address of a host at the network layer. To send a network layer packet to a
destination host, the dev
d estination host or the next hop. To this end, the IP address must be resolved into the corresponding
data link layer address.
Unless otherwise stated, a data link layer address in this chapter refers to a 48-bit Ethernet MAC
a ddress.
ARP Message Format
AR P messages are classified as ARP request messages and ARP reply messages.
illus trates the format of these two types of ARP messages.
As for an ARP request, all the fields excep
hardware address of the receiver is what the sender requests for.
As for an ARP reply, all the fields are set.
, go to these sections for information you are interested in:
amples
ice must know the data link layer address (MAC address, for example) of the
36-1
t the hardware address of the receiver field are set. The
Figure 36-1