Ethernet Frame

Before Bit Transmission on a RJ-45 starts, Data is encapsulated in the Data Layer using the Ethernet Protocol Encapsulation.

Ethernet Jargon

Ethernet protocol uses FCS which has different jargon than Frames that use CRC

Structure

  • Premable: Used for synchronization
  • Start Frame Delimitter: Signifies that next byte is start of destination address
  • Destination MAC address: Signifies destination
  • Source MAC address: Signifies source
  • Ethernet Type: IPv4,IPv6,SNA,DECnet,AppleTalk,etc…

Payload

The middle is the payload data

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