A network diagram will help organizations and teams visualize how devices like computers, and networks like telecommunications, work together. Network diagrams help paint a picture of how these operational networks function and they identify components like routers, firewalls and devices, and visually show how they intersect. This blueprint acts as a road map to allow professionals to do things like understand and troubleshoot issues and errors, expand networks, and maintain security and compliance.
Your organization can utilize network diagrams as granular or as broad as needed, showing individual devices, a single application, or just areas where services exist.
Why use network diagramming
Whether you need to update an existing network or plan a new one, with the ability to visualize networks, you can see how and where interactions occur, track components, and explore options. In addition, network mapping can help you:
- Troubleshoot bugs, errors and issues
- Avoid IT clutter
- Maintain security and compliance
- Outline the steps for completing a project
- Sell network-related projects to stakeholders
- Document internal and external communication
- Send potential vendors RFPs without including sensitive or confidential information
Logical vs. physical network diagrams
There are two types of network diagramming, logical and physical. Therefore, it’s essential to understand the differences so you can choose the right kind of mapping for each aspect of your organization.
A logical network diagram illustrates the flow of information through a network and shows how devices communicate with each other. It typically includes elements like subnets, network objects and devices, routing protocols and domains, voice gateways, traffic flow and network segments. In logical network diagrams, there are pivots for small, medium and large networks, where network diagram templates can be helpful.
Think of physical network mapping like a floor plan. It shows all of the physical aspects and arrangement of the network, including ports, cables, racks and servers, as well as any other hardware or devices that apply.
Both types of network diagrams have their place, and you’ll probably use both. But which one you use, and when, all depends on your network topology.
Topology refers to the arrangement of physical or logical aspects of your network. While there exists a wide range of derivations in topologies, they generally all stem from four basic formats: Bus, Ring, Star and Mesh.
It’s worth noting that some types are better suited to physical mapping, while others work best for logical network diagrams. And the kind of topology you choose can affect the performance and stability of your network, so it’s important to understand your options before diagramming your network. To that end, let’s take a look at the most common types of topologies and the type of mapping that works best for each.
Bus topology (logical)
Sometimes called line, linear, backbone or ethernet topology, a Bus topology connects each computer via a cable to a central “bus” with exactly two endpoints. In other words, if the central “bus” breaks down, the entire network breaks down.
- Great for small networks
- Easiest topology for connecting computers and devices in a linear fashion
- Requires less cable than some other topologies
- If the central “bus” breaks down, your network goes down, which can leave you without access to important files and information at critical times.
- Troubleshooting can be difficult
- Not ideal for large networks
- The more devices connected, the slower the network may become
Ring topology (logical)
In this network configuration, devices connect via a circular path, so each networked device is linked by two others in a “ring network.” So, when data packets transmit to one device, they have to travel through the ring until they’ve reached their destination. Most ring topologies are unidirectional, meaning that data can only move in one direction. Also, bidirectional (two-way data travel) networks are possible.
- When all data flows in one direction, the odds of having packet collision are eliminated
- Fast data transfers between workstations
- Adding workstations doesn’t impact network performance
- Doesn’t require a network server to control network connectivity between workstations
- All data passes through each workstation on the network, which can cause a slowdown
- If one workstation shuts down, it can impact the entire network
- The hardware needed to connect workstations to the network can be expensive
Star topology (physical)
The star topology features a central hub or switch that acts as a server, with the peripheral devices acting as clients. All data passes through the hub or switch before going to the connected device.
- Centralized network management
- Easy to add computers to the network
- Improved reliability because individual devices won’t impact the whole network
- If the central hub or switch fails, the entire network goes down
- Primary network device controls performance and the number of nodes the network can handle
- Costs for cabling and switches or routers can be high
Mesh topology (physical and logical)
Generally used for wireless networks, mesh topology connects computers and network devices. In full mesh topology, all nodes are connected, while with a partial mesh topology, at least two nodes in the network are connected to multiple other nodes in that network.
- Several devices can transmit data simultaneously so that the network can manage high levels of traffic
- Remains stable even when one device fails
- Adding devices won’t disrupt data transmissions between devices
- The cost to implement mesh networks can be high when compared to other topologies
- Topology development and maintenance can be challenging
- High likelihood of redundant connections, which can reduce efficiencies and increase costs
In addition to the four main topologies, there are also hybrid topologies that combine at least two topologies to form something new. Hybridization makes it possible to gain the strengths of the topologies and reduce the disadvantages of each. For instance, by combining a bus and mesh technology, you’ll get a tree topology. However, you can also combine star and ring topologies, star and bus topologies, and use other combinations to get the performance you need. The possibilities are virtually endless.
5 common steps to create network diagrams
Whether you’re creating a relatively simple network or building a complex network with a lot of “moving parts,” a diagram can help you visualize how the pieces will work together before making any actual connections. But you need to start with a goal, so if you’re not sure what you need the network to do, spend some time thinking about its purpose, talk to those who will use it or research how others have solved similar problems. Once you have a clear goal in mind, you can start your network diagram.
1. List the components
Start mapping your network by listing all of the equipment you’ll need. Be sure to include things like workstations, mainframes, hubs, servers, routers, firewalls and other components that you’ll need to make your network work. When doing this, leave nothing out. (Note: if the list starts to become unwieldy, you can create several diagrams, with one diagram devoted to a different facet of the project. This way, you won’t become overwhelmed and your diagram will be easier to navigate.)
2. Arrange your diagram
Once you understand what your network needs, you can start laying out your diagram and placing related physical or logical shapes near each other. This step is where your diagram starts to take shape.
3. Add connections
By placing a line between two shapes, you can show how those two elements are connected. Lines usually denote how information will flow, but a line can be used to display any connection that’s important to your network. Just make sure you know what each line means. (If necessary, creating a legend can help.)
4. Label your shapes
Make it easy for you and others to understand the symbols you’ve included in your network diagram by labeling them. Be sure to include any relevant details about the component next to the shape or you can number them and add the details in a reference guide or legend.
5. Format the diagram
Because you will use your network diagram, presented to stakeholders and used as a reference point by others, it should look professional and be easy to follow. So, make sure your diagram is clear, the connections are correct throughout; there are no missing components and that the right information is attached to the right shape. And don’t forget to adjust the sizes and colors of each shape as needed.
The value of network diagrams
A network is all about making the correct connections, delivering the right information at the appropriate time and helping people work more efficiently. And through network diagramming, you can plan your network, see the gaps, identify problems (and solutions) and find ways for your network to stretch and grow along with the company it supports. With that in mind, they can be invaluable tools for organizations of every size. To learn more, check out this step-by-step guide for creating network diagrams with software.