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Infrared
              Infrared transmission is used for short-range communication. Between 300 GHz and 400 THz is the infrared spectrum’s
              frequency region. It is employed for close-quarters contact, such as data transfer between two cell phones, TV remote
              control operation, and data transfer between a computer and a cell phone. The data rate will be very high because
              it allows a large amount of bandwidth. The walls block the passage of infrared radiation. Thus, the adjacent rooms
              cannot interfere with infrared communication taking place in one room.














                               Television                       Infrared Radiations                Remote


                 1.5 NETWORK TOPOLOGIES

              Everyone wants a fast, reliable internet connection, but businesses need it even more. Businesses may encounter
              downtime,  an  unpredictable  connection,  and  an  overall  frustrating  work  experience  if  they  do  not  have  a  high-
              performing network. All of these circumstances may push the business to incur needless expenses. Of course, a decent
              connection starts with your internet provider, but there are several additional aspects to consider.
              First and foremost, do you have a wireless, wired, or hybrid network? There’s no denying that connecting wirelessly
              is more convenient, especially now that wireless carriers, routers, and modems have advanced dramatically. Wireless
              networks, on the other hand, are more prone to interference. Wired networks provide the highest possible connection,
              security, and dependability. Although employing a wired network is sufficient, you must also take into account the
              many forms of network topologies. A topology describes how devices (or nodes) are connected. Different types of
              network topologies are as follows:


                                                           Network Topologies






                           BUS                RING               STAR              MESH               TREE
              The above topologies are categorised into two categories:

              Ð ÐBroadcast Topology: All nodes in a broadcast topology share the same physical link. All nodes receive when one
                 broadcasts. When more than one node transmits at the same time, there is a collision resolution mechanism in
                 place to handle it. Examples of broadcast topology are bus and ring.

              Ð ÐPoint-to-Point Topology: Every pair of nodes in a point-to-point topology has its own dedicated link. Example of
                 point-to-point topology are star and mesh.

              Bus Topology


              A bus topology, by definition, nodes need to be connected in a linear order. In a bus topology system, each device
              is connected to a single wire. It’s important to realise that a bus and linear topology do not transport data in both
              directions. In other words, data can only travel in one direction. A bus topology, like all other topologies, has advantages
              and disadvantages.

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