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:
“... God allows the wheat and the tares to grow up together, and ... the tares frequently get the start of the wheat and kill it out. The only difference between the wheat and human beings is that the latter have intellect and ought to combine and pull out the tares, root and branch.”
—Susan B. Anthony (1820–1906)
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—Henry David Thoreau (1817–1862)