Topologies

P2P

A Point to Point (P2P) topology is not a network, although a network can be used to create such a system. A P2P system includes only two locations with a fixed multi-channel connection. A distribution device such as a splitter or a matrix router can be used to include more locations in the system.

Daisy chain

Daisy chain is a simple topology that connects devices serially. An advantage of this topology is that the routing of network information is relatively simple and therefore fast. A disadvantage of daisy chain topology is the system behavior in case of a failure of a device in the chain. If one device fails the system is cut into two parts, without any connection between the two.

Ring

A ring topology is a daisy chain where the last device is connected to the first forming a ring. As all devices connected to the ring can reach other devices in two directions, redundancy is built in. If a device fails only that device is disabled. For additional redundancy a double ring can be used.

Star

As a star topology makes the most efficient use of a network’s bandwidth, most information networks are designed as a star. The center of a star carrying the highest network information traffic can be designed with extra processing power and redundancy, while the far ends of a star network can do with much lower processing power. Variations of a star topology are ‘tree’ and ‘star of stars’. A star topology also offers easy expansion, new locations can be connected anywhere in the network. A downside is the important role of the center star location as all network information to and from connected devices runs through it. If it fails a large portion of the network is affected. A network using a star topology can be made redundant using the Ethernet Spanning Tree Protocol.

Which is the right topology for you?

For every individual application one or a combination of these four topologies is most appropriate. Decision parameters include the number of locations, channel count, latency, desirable system costs, reliability, expandability, open or closed, standard Ethernet technology or proprietary systems etc. To make a decision on choosing the topology, a certain degree of expertise on networking technology is required, often found in an external consultant or a qualified system integrator such as Team Cnet of CnetLabs.