<Ethernet header>
Ethernet 2 header is the first image and is most common ethernet header format in today.
| Field | Description |
| Preamble | It informs that an Ethernet data will be transmitted. It is not displayed by packet sniffing.
* 10101010*7 + 10101011(SFD)
|
| SFD(Start of Frame Delimiter) | This is the last byte of the preamble, which informs that meaningful data is coming. |
| Destination MAC | This is the destination MAC address to send data. |
| Source MAC | This is the source MAC address which the data started. |
| Ether type | Types of the upper Protocol.
* 0x0800 : IPv4
* 0x0806 : ARP
|
| Payload | Data transmitted by Ethernet. 46 ~ 1500 bytes. |
| FCS(Frame Check Sequence = Trailer) | It check corrupted data within the entire frame to ensure integrity. |
* Ethernet frame means the range of Destination address ~ FCS.
* The maximum length of Ethernet frame is 1518(14+1500+4).