Creating a Network Topology Diagram: A Step-by-Step Guide
A Network Topology Diagram is one of the most valuable tools for visualizing your network’s structure and connections. Whether you are planning an upgrade, documenting your infrastructure for compliance, or troubleshooting connectivity issues, creating an accurate, up-to-date diagram can dramatically improve efficiency and reduce risks.
In this guide, we’ll show you how to draw a Network Topology Diagram, covering both manual and automated methods. We’ll explain the key components you should include, how the first three layers of the OSI model impact Network Topology Diagrams, and how topology diagrams can help you meet PCI compliance requirements.
You can also download a free trial to see how automated network mapping works in real-time!
Table of contents:
This article covers how to make a network topology diagram or map to plot out the endpoints on your network:
- How to create a diagram showing the topology of your network
- Manual vs. automated methods: which to use
- Manual mapping
- Automated mapping
- What’s included in a Network Topology Diagram
- Understanding OSI layer mapping (first 3 layers explained)
- Final thoughts
How to create a diagram showing the topology of your network
The primary goal of a Network Topology Diagram is to illustrate how devices connect to each other and to the internet. Your diagram should capture routers, switches, computers, servers, firewalls, wireless access points, and other infrastructure elements. It should also clearly show how each of these devices is linked and structured within the network.
Depending on the size and complexity of your environment, you can create a diagram manually or automate the process using specialized tools.
Manual vs. automated methods: which to use
Manual mapping
For smaller or simpler networks, manually creating a diagram remains a practical option. Start by listing all network devices, including routers, switches, servers, endpoints, and access points. Using a diagramming tool such as Microsoft Visio or Lucidchart, represent each device visually and label them with relevant details like IP addresses or port numbers. Draw lines to represent how devices are physically or logically connected and regularly review the diagram to keep it accurate.
However, manual methods have significant limitations. In dynamic environments, diagrams can quickly become outdated. As managed service providers (MSPs) grow and take on more clients, the number of networks they must manage increases substantially. Creating and maintaining manual diagrams for each network becomes extremely time-consuming, if not impossible. This also diverts valuable engineering time away from critical day-to-day operations, impacting productivity and efficiency.
Automated mapping
Automated mapping offers a much more scalable solution. Tools like Domotz automatically discover all devices and connections in real time, providing an instant visualization of physical and logical layouts. These diagrams stay continuously updated as networks change and can be easily exported for compliance reporting and documentation needs.
Automation reduces errors, saves time, and ensures diagrams remain reliable even in highly dynamic environments. For most IT teams, automated network mapping not only improves operational efficiency but also strengthens compliance readiness and minimizes associated risks.
What’s included in a Network Topology Diagram
An effective Network Topology Diagram does more than simply show a list of devices. It captures essential infrastructure such as routers, switches, firewalls, and wireless access points, along with endpoints like personal computers, laptops, smartphones, printers, and IoT devices. Connections to cloud services and remote sites should also be included to fully represent the network structure.
Diagrams should contain device metadata like IP addresses, MAC addresses, and VLAN identifiers to add context. Different connection types must be distinguished: direct links represent physical wiring, Wi-Fi links capture wireless associations, manual links indicate user-defined relationships, and outdated links highlight devices that are no longer active.
A comprehensive, clearly labeled diagram enables teams to manage and troubleshoot their networks more efficiently.
Understanding OSI layer mapping (first 3 layers explained)
Building a detailed Network Topology Diagram is easier when you understand how the first three layers of the OSI model contribute to network structure.
Layer 1, the Physical layer, includes cables, ports, and other tangible connections between devices. This layer answers the basic question: how are devices physically linked?
Layer 2, the Data Link layer, reveals deeper connectivity details such as MAC addresses, switch port assignments, and VLAN configurations, helping explain how data travels across a local segment.
Layer 3, the Network layer, introduces logical information, including IP addresses, subnets, and routing paths between segments and external networks.
Although some organizations maintain separate diagrams for each OSI layer, modern tools like Domotz combine them into a unified map. This not only saves time but also dramatically improves troubleshooting speed, as teams can see both physical and logical paths at a glance. Faster visibility into device relationships makes diagnosing and resolving network issues significantly more efficient.
Using Network Topology Diagrams for PCI compliance
For organizations handling cardholder data, maintaining an accurate and up-to-date Network Topology Diagram is a core requirement under PCI DSS standards. These diagrams must document the Cardholder Data Environment (CDE), illustrate how CDE systems are segmented from non-CDE systems, and provide comprehensive visibility into network infrastructure for audits and incident response.
Automated network mapping solutions help meet these requirements by keeping diagrams current in real time. They minimize manual effort and reduce the risk of outdated documentation. More importantly, they help minimize compliance risks by ensuring that the network’s true structure is always reflected accurately, supporting faster, smoother audit processes.
By adopting automated topology mapping, organizations strengthen their overall security posture and ensure ongoing alignment with PCI DSS standards.
Final thoughts
Network Topology Diagrams are essential tools for modern IT and compliance management. They allow organizations to plan, document, troubleshoot, and scale their networks more effectively. Manual methods still have a place for small, static networks, but for dynamic environments, automated mapping is the clear best choice.
Automated Network Topology Diagrams provide real-time visibility, smarter documentation, and critical support for maintaining compliance while minimizing associated risks.
Further reading
