LAN Topology Types

In the next three sections I will explain the three different network topologies you need to know for the exam. A network topology is all the combined physical, logical, or virtual components that make up the network or network segment. Although there are many topologies, we will focus on those necessary for the exam, which include the bus, ring, and star topologies.

Bus

A bus topology is a local area network (LAN) where each of the networked devices are attached to a single cable or link

In a bus topology, stations are attached to a linear multiport medium where only half-duplex operations exist between a station and a bus.

Ring

In a ring topology LAN in a bus topology LAN, all the nodes or devices in the network are attached to the network on the same cable or link. The difference is that a ring topology makes a complete circle. Both Token Ring/IEEE and Fiber Distributed Data Interface (FDDI) use a ring topology. FDDI is an American National Standard Institute (ANSI) X3T9.5 standard cable, which now supports up to Gigabit speeds using fiber-optic cabling. It can use a single ring for half-duplex operations or a dual–ring architecture for full-duplex operations.

Star

The star topology is the most common topology in today's networks, and includes Ethernet, Fast Ethernet, and Gigabit Ethernet. Each node in a star topology connects to a dedicated link where the other end connects to a switch or hub.