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ethernet pdu session

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Ethernet is a widely used networking protocol that operates at the data link layer of the OSI model. It's the most common LAN (Local Area Network) technology. Ethernet frames are the basic units of data transmission in an Ethernet network.

Here is a breakdown of a typical Ethernet frame:

  1. Preamble: The preamble is a sequence of bits that signals the start of the frame. It helps the receiving device synchronize its clock with the incoming signal.
  2. Start Frame Delimiter (SFD): The SFD immediately follows the preamble and marks the end of the preamble. It indicates the beginning of the frame's actual data.
  3. Destination MAC Address: This field contains the MAC (Media Access Control) address of the device for which the frame is intended.
  4. Source MAC Address: This field contains the MAC address of the sender.
  5. EtherType or Length: In Ethernet II frames, this field specifies the type of payload, indicating what protocol is being used in the data field. In IEEE 802.3 frames, this field indicates the length of the payload.
  6. Payload/Data: This is where the actual data being transmitted is placed. The type and structure of the data depend on the protocol indicated in the EtherType field.
  7. Frame Check Sequence (FCS): The FCS is a field used for error-checking. It contains a checksum or CRC (Cyclic Redundancy Check) value that allows the recipient to verify the integrity of the received frame.
  8. Inter-Frame Gap (IFG): This is a period of time between the end of one frame and the beginning of the next. It allows devices on the network to distinguish between the end of one frame and the start of another.