Software is always changing, but hardware not so much. This two-part tour introduces networking hardware, from traditional switches and routers to smartphones and wireless hotspots.
Local Area Network
The traditional local area network is connected with an Ethernet switch and Cat cables. The basic components of an Ethernetwork are network interface cards (NICs), cables, and switches. NICs and switches have little status lights that tell you if there is a connection, and the speed of the connection. Each computer needs an NIC, which connects to a switch via an Ethernet cable. Figure 1 shows a simple LAN: two computers connected via a switch, and a wireless access point routed into the wired LAN.
Installing cable is a bit of work, and you lose portability, but wired Ethernet has some advantages. It is immune to the types of interference that mess up wireless networks (microwave ovens, cordless phones, wireless speakers, physical barriers), and it is immune to wireless snooping. Even in this glorious year 2017 of the new millennium there are still Linux distributions, and devices like IP surveillance cameras and set-top boxes, that require a wired network connection for the initial setup, even if they also support wi-fi. Any device that has one of those little physical factory-reset switches that you poke with a paperclip has a hard-coded wired Ethernet address.