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:
“The writer in me can look as far as an African-American woman and stop. Often that writer looks through the African-American woman. Race is a layer of being, but not a culmination.”
—Thylias Moss, African American poet. As quoted in the Wall Street Journal (May 12, 1994)
“The most striking aspect of linguistic competence is what we may call the ‘creativity of language,’ that is, the speaker’s ability to produce new sentences, sentences that are immediately understood by other speakers although they bear no physical resemblance to sentences which are ‘familiar.’”
—Noam Chomsky (b. 1928)