This diagram illustrates several common forms of wiring in computer networks. In many homes, twisted-pair Ethernet cables are often used to connect computers. Phone or cable TV lines in turn connect the home LAN to the Internet Service Provider (ISP). ISPs, larger schools and businesses often stack their computer equipment in racks (as shown), and they use a mix of different kinds of cable to join this equipment to LANs and to the Internet. Much of the Internet uses high-speed fiber optic cable to send traffic long distances underground, but twisted pair and coaxial cable can also be used for leased lines and in more remote areas.

Related References - Ethernet Overview, Network Cables
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