What is Physical Transmission Media ?

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Physical Transmission Media - Wire, cable, and other tangible (touchable) materials used to send communications signals.

Type


1. Twisted pair cable - consists of one or more twisted pair wires bundles together. Each cable has two separate copper wires that are twisted together. These wires are twisted together to reduce noise.

* Noise – an electrical disturbance that can degrade communication.

2. Coaxial cable - usually referred as coax, consists of a single copper wire surrounded by at least three layers :

(a) insulating material
(b) a woven or braided metal
(c) a plastic outer coating

Cable TV wiring usually uses coaxial cable because it can be cabled over longer distances than twisted pair cable.

3. Fiber-optic Cable – consists of dozens or hundreds of thin strands of glass or plastic that use light to transmit signals. Each strand called an optical fiber is as thin as a human hair.

Inside the fiber-optic cable, an insulating glass cladding and a protective coating surround each optical fiber.

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