What is network topology?

Multiple PCs connected on a network

Network administrators may not completely understand the breadth of configurations at their disposal, with each one established for varying reasons, and capable of rendering different results. Therefore, it’s essential that network administrators pick the right network topology to suit their goals.

Network topology amounts to the different physical and logical configurations and comprises numerous ways of laying out a network.

Different topologies can, in essence, affect factors like the speed the network provides employees with, as well as its range. It’s crucial for businesses to understand the most appropriate topology to adopt in order to maximise the potential of networking.

Physical topology may refer to the geographical mapping of nodes that form a network, including routers, cables, switches and the software that supports switches and routers. Logical topology, meanwhile, encompasses the way in which signals can behave on a network, and alter the manner by which data flows.

Bus topology

The standard topology is known as 'bus' which involves all nodes tying together with a single backbone cable, which then provides service to every device on the network. It is one of the easiest network types to establish, with few drawbacks, but it isn't completely fool-proof. Adding too many devices to a bus network, for instance, can lead to serious problems. The overall speed can be hampered as the network spin becomes more crowded. This is partly why bus topologies are seen as fragile and more likely to incur failures.

Star topology

Star is arguably the most popular network topology for users. It's a network where all the nodes of a connection are linked to a central point like a router. Its popularity is partly due to its simple one-to-one ratio set up of devices to cables. Each device only needs one port but it does often mean the price of installation is higher than other network types.

A variation of this is a 'Tree' topology which is an evolution of the star model. It involves multiple star networks liked together via a central bus. These are largely regarded as a scalable topology because it is easy to expand with additional star networks.

Ring topology

Essentially a bus network that loops around and connects to itself, ring topologies are peer-to-peer networks in which each node is connected to its immediate neighbour on either side, with data travelling around the ring in one direction until it reaches the correct node. As with bus networks, the failure of a single node will cause an outage across the entire network, and poor bandwidth on one inter-node link will bottleneck the whole system. On the other hand, this form of network doesn't require a server to administrate it and performs better under load than bus networks.

Mesh topology

One of the most advanced forms of network is mesh topology, which is when there is more than one connection between nodes. This can be a full mesh' topology, in which every node is linked to every other node, or a partial mesh, in which only some nodes utilise multiple connections. A mesh topology benefits from being robust and easily diagnosable when things go wrong, but the installation can be difficult and the cost of maintaining it can be high.

Hybrid

A hybrid topology is one that uses two or more different network topologies. These can include a mix of bus, mesh, ring or star topology. Choosing a hybrid topology over a more standard one will largely depend on the needs of the user, whether that's a school, a business or even personal use. The number of computers, the location and desired network performance will all need to be assessed in the decision.

Adam Shepherd

Adam Shepherd has been a technology journalist since 2015, covering everything from cloud storage and security, to smartphones and servers. Over the course of his career, he’s seen the spread of 5G, the growing ubiquity of wireless devices, and the start of the connected revolution. He’s also been to more trade shows and technology conferences than he cares to count.

Adam is an avid follower of the latest hardware innovations, and he is never happier than when tinkering with complex network configurations, or exploring a new Linux distro. He was also previously a co-host on the ITPro Podcast, where he was often found ranting about his love of strange gadgets, his disdain for Windows Mobile, and everything in between.

You can find Adam tweeting about enterprise technology (or more often bad jokes) @AdamShepherUK.