We compared the three major categories of cable types: coaxial, twisted pair, and fiber optic. Each cable type has varying performance characteristics, with coaxial being the most limiting cable and fiber optic having the greatest signal carrying potential. After we described these two primary physical elements of network topologies, we examined the various topology design configurations.

Bus is a commonly used topology in small networks. Although prevalent for a number of years in Ethernet networks, it has been largely replaced by star configurations. Nodes attach to a central coaxial cable, the bus, and access other nodes attached to the bus by sending information across the common bus to the correct device.

Star topology is currently the most popular way to layout a network. Star topology forms a star, in that a hub is at the physical and logical center of the network. From the hub, cable fans out to the end-user computer or nodes to form a star pattern. Star topology isolates a node, such that if a node has a problem it does not necessarily affect the rest of the computers on that network.

Ring topology is primarily used in networks to connect groups of nodes to a common point of connectivity referred to as a backbone. Older rings consist of a single point-to-point link connecting devices. A break in one of the links would take the entire network down. Newer ring topologies have dual rings that provide for higher reliability and redundancy in case one of the links goes down.

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