Structure
A data packet on the wire is called a frame and consists of binary data. Data on Ethernet is transmitted most-significant byte first. Within each byte, however, the least-significant bit is transmitted first.
The table below shows the complete Ethernet frame, as transmitted, for the payload size up to the MTU of 1500 octets. Some implementations of Gigabit Ethernet (and higher speed ethernets) support larger frames, known as jumbo frames.
| Preamble | Start of frame delimiter | MAC destination | MAC source | 802.1Q tag (optional) | Ethertype (Ethernet II) or length (IEEE 802.3) | Payload | Frame check sequence (32‑bit CRC) | Interframe gap |
|---|---|---|---|---|---|---|---|---|
| 7 octets | 1 octet | 6 octets | 6 octets | (4 octets) | 2 octets | 42–1500 octets | 4 octets | 12 octets |
| ← 64–1522 octets → | ||||||||
| ← 72–1530 octets → | ||||||||
| ← 84–1542 octets → | ||||||||
Read more about this topic: Ethernet Frame
Famous quotes containing the word structure:
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—Friedrich Nietzsche (1844–1900)
“I’m a Sunday School teacher, and I’ve always known that the structure of law is founded on the Christian ethic that you shall love the Lord your God and your neighbor as yourself—a very high and perfect standard. We all know the fallibility of man, and the contentions in society, as described by Reinhold Niebuhr and many others, don’t permit us to achieve perfection.”
—Jimmy Carter (James Earl Carter, Jr.)
“There is no such thing as a language, not if a language is anything like what many philosophers and linguists have supposed. There is therefore no such thing to be learned, mastered, or born with. We must give up the idea of a clearly defined shared structure which language-users acquire and then apply to cases.”
—Donald Davidson (b. 1917)