lecture_4_-_transmission_media_-_part1.pptx

-_transmission_media_-_part1.pptx
lecture_4_-_transmission_media_-_part1.pptx

1. Physical Transmission NETWORKING 1

2. The transmission of data from one  computer  to another, or from one device to another. A   communications  device, therefore, is any machine that assists data transmission. For example, modems, cables, and ports are all  communications devices 2 Computer Communication

3. Anything that can carry information from a source to a destination or from one point to other point. 3 Transmission Media/Channel/Link

4. 4 Physical Transmission

5. There are two categories of Transmission media : Wired (Guided) media In wired media, communication devices are directly connected with each other by  using some physical media like wires . Wireless (Unguided) media Unguided media transport signals without using a physical media. 5 Transmission Media

6. For Guided Medium The medium is more important For Unguided The bandwidth produced by the antenna is more important 6 Overview

7. Bandwidth : The amount of data that can be transferred through a communication medium in a given time is called bandwidth . The bandwidth of digital signal is measured in bits per second 0" Bytes per second.   7 Design Factors for Transmission Media

8. 1. Wired (Guided) media 8

9. There are three categories of guided media: Twisted Pair : Unshielded twisted pair (UTP) Shielded twisted pair (STP) Coaxial Cable Fiber Optic Cable 9 I. Wired (Guided) media:

10. Twisted pair is the most commonly used physical transmission medium. It is used in local area network to connect computers and other devices. Twisted pair cable consists of copper wires. The pair of wires is covered by a Plastic insulation and it is twisted together. Twisting of Wires Protects them from interference by external electromagnetic waves.  Low frequency transmission medium 10 Twisted Pair Wires

11. STP (shielded twisted pair) the pair is wrapped with metallic foil or braid to prevent the pair from electromagnetic interference UTP (unshielded twisted pair) each wire is insulated with plastic wrap, but the pair is encased in an outer covering 11 Types of Twisted Pair

12. 12 Twisted Pair Cable

13. Twisted Pair Advantages & Disadvantages Advantages Disadvantages Inexpensive and available Flexible and light weight Easy to work with and install Sensitivity to interference and noise Relatively low bandwidth (3000Hz) 13

14. Carries signals of higher frequency ranges than twisted pair cable. Has an inner conductor I nner conductor is enclosed in an insulator, which is again enclosed in an outer conductor of metal braided mesh. Used for cable television, LANs, telephony 14 Coaxial Cable (or Coax)

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16. Optical fiber is made of glass or plastic and transmits signals in the form of light . The cable consists of a strand of glass ( core) surrounded by a glass tube ( cladding ). Its surrounded by a plastic isolation layer for protection . 16 Fiber Optic Cable

17. Relatively new transmission medium used by telephone companies in place of long-distance trunk lines Fiber Optic works on the properties of light From one end of it light is emitted, it travels through it and at the other end light detector detects light stream and converts it to electric data form. Fiber Optic provides the highest mode of speed.  17 Fiber Optic Cable

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