Review: Ethernet Frame

 On my practice quizzes, I'm consistently getting the Ethernet Frame questions wrong. Time for a review!  

This is from the Data-Link-Layer.  Layer 1.  

Ethernet uses 48-bit MAC Address.  First 24 is the OUI (assigned by mfr) and last 24 is vendor assigned.




Preamble: 64 bit header

Recipient's Destination Address  6 bytes

Sender Mac Address 6 bytes

Type/Length 2 bytes

Data Field: Payload IP Packet/ limit is 46 to 1500 bytes

Pad: minim size is 64 bytes

FCS: Frame Check Sequence. 4 bytes. Helps the nodes know when data has been corrupted. Devices on a network have to be able to know when errors occur. Also called "the trailer."  

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