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Communication
                          Video Session                                                                 Subject Enrichment


                     Scan the QR code or visit the following link to watch the video: Types of Networks
                     https://www.youtube.com/watch?v=5qgpQ4CmZxU
                     Now answer the following questions:
                     1.  Can 100 computers be connected on a LAN?
                        .....................................................................................................................................................................................
                     2.  What kind of network is formed by connecting the devices in our homes?
                         .....................................................................................................................................................................................

                     3.  In which network does physical distance have no effect?
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                   1.4 TRANSMISSION MEDIUM
                 In data communication, a transmission medium is defined as a pathway between a sender and receiver. In other
                 words,  it  is  a  way  through  which  information  is  transmitted  from  one  computer  to  another  computer.  Another
                 name for transmission medium is communication channel. The data is transmitted in the form of signals through
                 communication channels. Signals change the data into suitable format for transmission medium. There are mainly two
                 types of transmission media which are as follows:

                 Ð ÐGuided Media                                     Ð ÐUnguided Media
                 Let us discuss about them in detail.

                 Guided Media
                 Guided media refers to the physical medium through which the signals are transmitted. It is also known as bounded or
                 wired media. Features of guided media are as follows:

                 Ð ÐIts speed is very high.
                 Ð ÐIt is secure.

                 Ð ÐIt is used for reasonably shorter distances.
                 There are mainly three types of guided media which are as follows:

                 Twisted Pair Cable
                 Twisted pair cables have two insulation-covered conductors, each of which is typically constructed of copper. Twisted
                 pair cables derive their name from the way these two conductors are twisted together. Due to their small size, these
                 cables are affordable and simple to install. They are typically used to transmit voice and data over short distances.
                 Compared to other types of cables, it is less expensive. However, these cables have less bandwidth.
                                                                                     Copper Conductor
                                         Twisted Pair









                                                                                Insulating material

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