Bus topology – This topology connects each computer, or station, to a single cable. At each end of the cable is a terminating resistor, or terminator. A transmission is passed back and forth along the cable, past the stations and between the two terminators, carrying a message from one end of the network to the other. As the message passes each station, the station checks its destination address. If the address in the message matches the station’s address, the station receives the message. If the addresses do not match, the bus carries the message to the next station, and so on.

Mesh network topology – Common in WANs, a mesh network connects remote sites over telecommunication links. Meshes use routers to search among multiple active paths (the mesh) and determine the best path for that particular moment.

Ring topology –The ring topology has computers on a circle of cable. The are not terminated ends. The data travels around the loop in one direction and passes through each computer. Each computer acts like a repeater to boost the signal and send it on. Because the signal passes through each computer, the failure of one computer can bring the entire network down. The ring may incorporate features which disconnect failed computers so that the network will continue to function despite the failure.

Star topology – In a star topology, each computer is connected by cable segments to a centralized component called a hub. Signals transmitted by a computer on the star pass through the hub to all computers on the network. This topology originated in the early days of computing with terminals connected to a centralized mainframe. The star offers centralized resources and management. However, because each computer is connected to a central point, this topology requires a lot of cable in a large installation, and if the central point fails, the entire network goes down.