Every network has a specific collection of nodes and links that connect them. The arrangement of those nodes and links, or the network topology, informs performance, maintenance costs, and more. You should know the network topology models in use today when designing or managing a network, including the ring, mesh, bus, star, and tree topologies. To effectively manage your network topology, it’s essential to stay on top of your network’s configurations, visually map your network, and monitor its performance.
While it’s possible to perform manual topology mapping, you get more for your time with an automated tool. I recommend SolarWinds® Network Topology Mapper (NTM), which offers automated device discovery and can generate detailed and easily digestible network topology maps, allowing you to view and understand your network more quickly and clearly.
What Is Network Topology?
A network’s topology details how the devices within it connect with one another and how data moves between its nodes. It can also be defined simply as a schematic description of a network’s elements’ arrangement.
While a logical network topology illustrates how data flows between your network’s devices, a physical network topology illustrates the physical connections within your network, such as its computers and cables. Visual diagrams can be used to represent logical and physical topologies, depending on your needs—either can be useful for understanding your network and its layout.
Why Is Network Topology Important?
Your network’s configuration, or topology, will affect its function and performance, so selecting the right topology for your organization is crucial. By choosing the topology best suited for your organization, its resources, and its needs, you can reduce operational costs, improve performance, and optimize resource allocation.
Using diagrams to understand your organization’s logical and physical network topologies will enable you to visualize how your network’s devices connect, helping you troubleshoot network slowdowns and connectivity issues quickly.
Types of Network Topology
There are several types of network topologies, each with advantages and disadvantages, so there’s no one-size-fits-all network topology solution. Understanding each topology’s strengths and weaknesses will enable you to make an informed decision and find a network topology that will better serve your organization in the long run.
Star Network Topology
As the name suggests, each device in this common topology connects to a central switch with coaxial cables, twisted pair cables, or optical fiber cables. Non-central nodes are also indirectly connected with one another through the central switch, or hub, which can serve as a repeater.
Advantages of Star Network Topology
Star topologies are easy to set up because each device only needs a single cable to connect to the central hub, so this topology requires fewer cables than others. Star topologies can also simplify the process of troubleshooting network performance problems. Since every network device connects to a single switch, this topology is easy to manage. You can easily add or remove nodes from the central switch without taking the entire network offline. Additionally, if a cable fails, only one device will be affected, offering these topologies protection against failures.
Disadvantages of Star Network Topology
Star network topologies rely on the central switch’s health and performance; when the central switch goes down, the rest of the network will follow. As a result, monitoring and managing the central switch is essential.
While it’s easy to add new devices to star topologies, it’s important to remember the central switch will have a limited number of ports, putting a fixed cap on the network’s size.
This topology requires fewer cables than other topologies, but you’ll still need to invest in the central switch, which can drive up installation costs.
Bus Network Topology
Within a bus network topology (also known as backbone network topology), the network’s nodes, or computer and network devices, are connected via drop lines to the common cable. Bus topologies are simple and allow for unidirectional data transmittance. A bus topology with two endpoints is called a linear bus topology.
Advantages of Bus Network Topology
Bus topology is the easiest and cheapest type of topology to install. With a one-to-one ratio of devices to drop lines, this topology requires less cable than other topologies, reducing the installation time and expenses. Adding new devices to the network is also straightforward. Just connect the new device to the central cable with a new drop line.
Given their simple layout, bus topologies aren’t usually used for office networks anymore and are, instead, best suited for small networks or consumer products.
Disadvantages of Bus Network Topology
While having a single cable makes bus topologies incredibly cost-effective, it also introduces several potential problems, including increased collisions, increased congestion, and low security. As a result, bus topologies are best for networks with low traffic volumes.
With a single point of failure, this topology isn’t very robust. If the common cable fails, then your entire network will crash. Additionally, as a half-duplex, data can only be transmitted in one direction along the cable at any given time, making congestion a common problem. As more network nodes begin to rely on the main cable, data transmission rates will slow.
Mesh Network Topology
Ideal for high-value, small to mid-sized networks, mesh topology consists of interconnected nodes, making it a fast and secure choice. In a full mesh network topology, each node is connected to all the other nodes via direct link, creating point-to-point connections. In a partial mesh topology, most nodes are interconnected, but some nodes only connect with a few others via point-to-point links.
Data transmitted within a mesh topology is sent through routing or flooding. With routing, the nodes determine the shortest distance to the packet’s destination using routing logic, while flooding involves sending the data to every node within the network.
Advantages of Mesh Network Topology
Mesh topology is quick, durable, and secure, thanks to the nodes’ interconnectivity. The mesh of nodes increases data transmission speed and ensures the network doesn’t have a single point of failure, increasing security and redundancy.
Disadvantages of Mesh Network Topology
As you might expect, it takes several cables to connect each node to all the other nodes, which means installing mesh topology can get expensive quickly, takes a considerable amount of time to set up, and requires a lot of configuration. Consequently, this topology is difficult to administer and costly to maintain. Your network’s size will also be limited by how many cables your computers can accommodate.
Ring Network Topology
As its name implies, ring topology consists of a ring of devices connected to two adjacent devices via point-to-point links, with the first and last nodes linking the loop. You can conveniently monitor your devices and configure the network through one node. Ring topologies are half-duplex, so data can only be sent in one direction at a time, and data will pass through each network node on its way to its target device.
In a ring topology, the node possessing the token is the only node capable of transmitting data, reducing the possibility of a collision. With early token release, the node releases the token as soon as it transmits the data, while with delayed token release, the node holds onto the token until it receives an acknowledgment from the receiver that the data has been received.
Advantages of Ring Network Topology
Thanks to its low installation costs, high data transmission rates, and low incidences of collision, many small businesses use a ring topology. It’s easy to manage, install, and expand, and it uses token-based protocols, which reduces the risk of packet collisions. Dual ring topologies are particularly redundant, providing continuity for the network.
Disadvantages of Ring Network Topology
This topology is vulnerable to failure, as if just one node fails, the entire network will go down. As a result, you’ll have to constantly monitor your ring topology network to ensure every node is functioning correctly, and you’ll have to shut the entire network down to add new nodes or alter any existing ones.
Since all your network’s devices will share bandwidth, it can be difficult to scale your network beyond a certain point without encountering performance issues. You’ll need to monitor the number of devices added to your network to ensure your bandwidth isn’t stretched too thin, causing communication delays.
Dual Ring Topology
Dual ring topologies function in the same manner as ring topologies with one key difference: they can send data in both directions, making them full-duplex and more efficient. Each node has two connections on both sides, enabling the transmission of data in both directions.
In addition to all the benefits ring topology offers, dual ring topology is redundant, thanks to the second ring, which can send data if the other ring fails.
Tree Network Topology
Named for its tree-like shape, the tree network topology has a hierarchical layout with at least three different levels. The tree topology consists of the central hub, secondary hubs, and devices. Data will flow from the central hub to a secondary hub to a device or from a device to a secondary hub to the central hub. The central hub serves as the sole mutual connection between the secondary hubs and their devices, creating parent-child dependencies.
Advantages of Tree Network Topology
Since the tree topology combines the bus and star topologies, it’s used in wide area networks (WANs) to support physically distanced devices. It’s also easy to manage and expand as your organization continues to grow. The tree topology’s hierarchical structure simplifies the troubleshooting process by allowing you to systematically check for performance issues within the network.
Disadvantages of Tree Network Topology
Between the monitoring software and the large amount of cabling needed, tree topology can get expensive. It’s also not very robust; if the central hub is compromised, the whole network may fail as the subtrees become partitioned. Therefore, it’s essential to invest in monitoring software if you have a large network.
This complicated network topology is difficult to manage and only becomes increasingly difficult to administer as more nodes are added. Consequently, this topology is better suited for networking experts.
Hybrid Network Topology
A hybrid topology combines two or more standard network topologies. A larger enterprise might opt to use a hybrid topology to allow various departments to employ different network topologies.
Advantages of Hybrid Network Topology
Though each hybrid topology’s advantages will be determined by which topologies are implemented, using a hybrid topology will generally give your organization flexibility and scalability. Therefore, they’re optimal for larger networks.
Disadvantages of Hybrid Network Topology
Again, each hybrid topology’s disadvantages will be determined by the topologies being employed. However, hybrid topologies are often complex and require professional management and monitoring software.
Which Topology Is Best for Your Network?
When considering which topology to use, you may be wondering What is the most common network topology? While other topologies were used more commonly in the past, these days the star topology is the most common.
However, it might not be the best topology for your network. Every organization’s networking needs will differ according to its size, budget, expertise, and needs. When trying to determine which topology is best for your network, consider your organization’s size, future expansion plans, goals, and budget.
Consider each topology’s scalability, cable length, and cable type. For example, the bus or ring topology might be best if you have a limited budget because they require fewer cables to install. If you’d prefer to have a more durable and secure topology, the mesh topology with its point-to-point connections might be a better fit. Ultimately, you should carefully compare your organization’s needs, plans, and resources with each topology’s requirements, advantages, and disadvantages.
What Tools Can Help Manage Network Topology?
Regardless of which network topology your organization uses, monitoring, managing, and mapping your topology is essential. Manually creating a network topology diagram can be a time-consuming and complicated process. I recommend using a tool for this.
With Microsoft Visio, Lucidchart, LibreOffice Draw, and more on the market, there are plenty of tools for network monitoring, mapping, and managing to choose from. However, my favorite topology mapping tool is the comprehensive SolarWinds Network Topology Mapper.
SolarWinds Network Topology Mapper (Free Trial)
With automated device discovery and mapping SolarWinds Network Topology Mapper (NTM) is a useful tool designed to make creating comprehensive network topology maps simple. You can easily manage, share, encrypt, and print maps with this intuitive network diagram software.
NTM was built to automatically plot your network using ICMP, SNMP, WMI, or CDP, and works with VMware and Microsoft Hyper-V, but users can also manually connect network devices and edit node details. NTM’s automatic scans and automated reports help ensure you’ll have current information about your network and its devices. With an up-to-date network diagram, your organization can better meet compliance requirements for SOX, PIC, HIPAA, and FIPS 140-2.
Start Mapping Your Network Topology Today
Given the way network performance is affected by its topology, it’s important to find the right topology for your organization’s needs—but the work doesn’t end there. By frequently scanning and mapping your network, you can perform inventory management of hardware assets and quickly detect topological changes.
The best way to map your network topology is with a convenient and thorough solution like NTM. Download a 14-day free trial of SolarWinds Network Topology Mapper today to gain a clear view of your network’s topology.