H3C Technologies H3C S3600 Series Switches - Manual (Page 596)

1-2
z As for an ARP reply, all the fields are set.
Figure 1-1 ARP message format
Hardware type (16 bits)
Protocol type (16 bits)
Length of hardware address Length of protocol address
Operator (16 bits)
Hardware address of the sender
IP address of the sender
Hardware address of the receiver
IP address of the receiver
Hardware type (16 bits) Hardware type (16 bits)
Protocol type (16 bits)
Length of hardware address Length of protocol address
Operator (16 bits)
Hardware address of the sender
IP address of the sender
Hardware address of the receiver
IP address of the receiver
Table 1-1 describes the fields of an ARP packet.
Table 1-1 Description on the fields of an ARP packet
Field Description
Hardware Type
Type of the hardware interface. Refer to Table
1-2 for the information about the field values.
Protocol type
Type of protocol address to be mapped. 0x0800
indicates an IP address.
Length of hardware address Hardware address length (in bytes)
Length of protocol address Protocol address length (in bytes)
Operator
Indicates the type of a data packets, which can
be:
1: ARP request packets
2: ARP reply packets
3: RARP request packets
4: RARP reply packets
Hardware address of the sender Hardware address of the sender
IP address of the sender IP address of the sender
Hardware address of the receiver
For an ARP request packet, this field is null.
For an ARP reply packet, this field carries the
hardware address of the receiver.
IP address of the receiver IP address of the receiver
Table 1-2 Description on the values of the hardware type field
Value Description
1 Ethernet
2 Experimental Ethernet