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    TRANSMISSION MEDIA

                     A transmission medium is the path or channel through which data travels from one device to another
                     in a network. It is essential for determining the speed, quality and reliability of the data transfer.

                                                          Types of Transmission  Media

                                 Guided (Wired) Media                               Unguided (Wireless) Media

                       Twisted Pair      Coaxial        Fibre Optic                                           Infrared
                          Cable           Cable            Cable          Radio Waves      Microwaves         Waves

                     GUIDED (WIRED) MEDIA

                     Guided  media uses  physical  cables  for data  transmission.  The different  types  of guided
                     media include:

                         Twisted pair cable: This type of cable consists of two copper wires
                        twisted  around each  other  to  reduce  interference.  Twisted  pair
                        cables are commonly used in telephone lines and LANs.
                                                  Coaxial cable: This topology contains, a single copper wire surrounded

                                                 by insulating layers and shielding to prevent signal loss. Coaxial cables
                                                 are typically used in cable TV and data communication.

                         Fibre optic cable: This cable uses light signals transmitted through
                        thin strands of glass or plastic  for  transmitting  data.  Fibre optic
                        cables  enable  noise-free  data  communication  at  high speed  over
                        long-distances.

                     UNGUIDED (WIRELESS) MEDIA

                     Unguided  media transmits  data  through the  air or
                     space  using  electromagnetic  waves. There are no          Transmitter                     Receiver
                     physical wires involved.

                     The different types of unguided media include:
                         Radio  waves: Radio waves are electromagnetic

                        signals  that  travel in all directions  and can pass
                        through walls.  They are used  in mobile  phones,
                        radios and wireless networks.

                         Microwaves: Microwaves  travel in straight  lines and require  line-of-sight communication
                        between antennas. They are used in satellite links, mobile communication and TV broadcasts.

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                                                                                                   Networks Around Us

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