Layer 1: Physical Layer
This layer deals with the physical plugs and sockets and electrical specification of signals.
This is the medium over which the digital signals are transmitted. It can be twisted pair, coaxial cable, optical fiber, wireless, or other transmission media.
Read more about this topic: OSI Protocols
Famous quotes containing the words layer and/or physical:
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—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
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—Marcus Tullius Cicero (106–43 B.C.)