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These resources may be hardware resources such as printers or software resources such as application programs or
            data. One of the computers often acts as a server and responds to requests from other computers. The computers
            requesting the server are called clients. For example, suppose you have a printer and a few computers. If all computers
            need a printer, they can access it via a LAN (see Figure 6.11 (a)).






















                         (a) LAN within a building                           (b) LAN within a campus




                                                            PC2




                                        PC3                       Router        PC1

                                                                   Switch or






                                       PC4


                                                                       PC5


                                                       Printer

                                                 Figure 6.11 Local Area Network (LAN)
            The  most  commonly  used  topologies  in  LANs  are  bus,  ring  and  star.  The  transmission  media  used  in  LANs  are
            twisted-pair, coaxial cable, and fibre optic. Figure 6.11 (a) shows a LAN within a building. Figure 6.11 (b) shows a LAN
            within a campus. LANs typically operate at speeds in the range of 10 Mbps to 1 Gbps.
            6.4.3 MAN

            A Metropolitan Area Network (MAN) can span a radius of up to 50 kilometres. A MAN typically  connects various local
            area networks within a city. A single organisation may own a MAN or it may be a public network that many individuals
            or organisations use. MANs usually operate at higher speeds than LANs. Typical transmission media for a MAN include
            Ethernet cable, microwave, radio wave, and fibre optic.







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