Media

The base of communications between devices is the physical layer of the OSI model. This is the domain of the actual connection between devices, whether by wire, fiber, or radio frequency waves. The physical layer separates the definitions and protocols required to transmit the signal physically between boxes from higher level protocols that deal with the details of the data itself. Four common methods are used to connect equipment at the physical layer:

  • Coaxial cable
  • Twisted-pair cable
  • Fiber-optics
  • Wireless

Coaxial Cable

Coaxial cable is familiar to many households as a method of connecting televisions to VCRs or to satellite or cable services. It is used because of its high bandwidth and shielding capabilities. Compared to standard twisted-pair ...

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