Ring Topology

Ring Topology
In the ring topology, each computer is connected directly to two other computers in the network. Data moves down a one-way path from one computer to another, as shown in Figure 1.7. The good news about laying out cable in a ring is that the cable design is simple. The bad news is that, as with bus topology, any break, such as adding or removing a computer, disrupts the entire network. Also, because you have to “break” the ring in order to add another station, it is very difficult to reconfigure without bringing down the whole network. For this reason, the physical ring topology is seldom used.

Note:

Although its name suggests a relationship, Token Ring does not use a physical
ring topology. It instead uses a physical star, logical ring topology (and runs at
speeds of either 4Mbps or 16Mbps). You will learn more about logical topologies
later in this chapter.

Example:

A typical ring topology

 A few pros and many cons are associated with a ring topology. On the pro side, the ring topology is relatively easy to troubleshoot. A station will know when a cable fault has occurred because it will stop receiving data from its upstream neighbor.
On the con side, a ring topology has the following characteristics:

• Expensive, because multiple cables are needed for each workstation.
• Difficult to reconfigure.
• Not fault tolerant. A single cable fault can bring down the entire network.