<ARP header>
| Field | Description |
| Hardware type | 2 layer protocol.
* Generally 1(Ethernet).
|
| Protocol Type | 3 layer protocol.
* Generally 0x0800(IPv4).
|
| Hardware address length | The length of the MAC address.
* Generally 6(Bytes).
|
| Protocol address length | The length of the IP address.
* Generally 4(Bytes).
|
| Operation code | ARP operation type.
1 : ARP request.
2 : ARP reply.
3 : RARP request.
4 : RARP reply.
|
| Source hardware address Target hardware address | MAC address. |
| Source protocol address Target protocol address | IP address. |