The Start Frame Delimiter (SFD) is the 8-bit (1-byte) value marking the end of the preamble of an Ethernet frame. The SFD is immediately followed by the destination MAC address. It has the value 10101011.
The preamble of an Ethernet frame consists of a 56-bit (7-byte) pattern of alternating 1 and 0 bits, which allows devices on the network to easily detect a new incoming frame. The SFD is designed to break this pattern, and signal the start of the actual frame.
Famous quotes containing the words start and/or frame:
“The mother may be doing ninety percent of the disciplining, but the father still must have a full-time acceptance of all the children. He never must say, “Get these kids out of here; I’m trying to watch TV.” If he ever does start saying this, he is liable to see one of his kids on the six o’clock news.”
—Bill Cosby (20th century)
“From Harmony, from heavenly Harmony
This universal Frame began:
From Harmony to Harmony
Through all the Compass of the Notes it ran,
The Diapason closing full in Man.”
—John Dryden (1631–1700)