A network is a physical group of computers wired together so that they can communicate directly with each other using the same data link protocol and without being connected by routers. For instance, any computer on an office Ethernet network can address any other computer on the network directly-there is no need to forward information between two different shared media networks (for instance, between an Ethernet and a token-ring network). Computers may be connected with hubs, switches, or bridges but remain a single network because data can be transmitted between any two computers over…

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Networks and Routing