System Diagrams

System diagrams are essential tools for visualizing the components of a system and how they interact.

They help IT professionals, network engineers, and developers understand how different hardware and network components work together.

In this lesson, we’ll learn about:

1. What a system diagram is and why it is important
2. The key components of a system diagram
3. How to draw a system diagram step by step
4. Completing worked examples based on real-world scenarios

A system diagram is a visual representation that shows how different components of a system are connected and interact.

These diagrams are commonly used in IT to plan, design, and troubleshoot networks and systems.

Why are system diagrams important?

• They provide a clear overview of system components and their relationships.
• They help in troubleshooting by identifying weak points in a system.
• They assist in planning and scaling IT infrastructure.
• They improve communication between IT teams & stakeholders.

A system diagram typically includes:

• Devices
• Network equipment
• Connections

Let’s look at each of these in more detail.

Devices

• Servers – Store and manage data or applications.
• Computers – Devices used by end-users to access the network.
• Printers – Devices connected to the network to produce hard copies.
• Mobile Devices – Smartphones and tablets that connect to the network.
• Smart TVs and Gaming Consoles – Often part of home networks and entertainment systems.

Network Equipment

• Routers – Direct traffic between networks and manage internet connections.
• Switches – Connect multiple devices within a network.
• Firewalls – Protect networks from unauthorized access.
• Access Points – Enable wireless devices to connect to the network.

Connections

• Wired connections (Ethernet cables, fiber optics)
• Wireless connections (Wi-Fi, Bluetooth, mobile data)

Step 1: Identify the Components

Before drawing, list all the components that will be part of the system.

This includes hardware (computers, servers, routers) and connections (wired or wireless).

Step 2: Arrange Components Logically

Start by placing the core components (such as switches & routers) at the centre and arrange end-user devices around them. Consider:

• Grouping similar devices together (e.g., by room).
• Placing network infrastructure like routers and switches centrally.
• Using clear labels for each component.

Step 3: Connect the Components

• Use solid lines to represent wired connections.
• Use dashed lines for wireless connections.
• Include arrows if data flow direction is important.
• Label the lines to identify the type of connection.

A Home Network for a Graphic Designer

Adam is a freelance graphic designer who works from home.

His study has a desktop PC and a printer. He uses the PC for designing and prints high-quality images. He also uses a smartphone for client meetings.

His home includes a living room with a gaming console and a smart TV.

Internet access is important for his work and leisure activities.

Step 1: Identify the Components

From the scenario, the key components in the home network are:

• Study: Desktop PC, printer, smartphone
• Living Room: Smart TV, Games console
• Network Equipment: Router

Step 2: Arrange Components Logically

The network should be arranged so that core devices (such as the router) are central, with other devices connecting logically based on location.

Step 3: Connect the Components

Wired Connections:

• Desktop PC to router (could be a wired ethernet connection but could be wireless)
• Games consoles to Smart TV (connected via an HDMI connection)
• Router to Internet Service Provider (fibre optic)

Wireless Connections:

• Printer to Desktop PC (Bluetooth or Wi-Fi)
• Smart TV to router (Wi-Fi)
• Smartphone to router (Wi-Fi)

A system diagram visually represents how hardware and network components interact.

System diagrams are useful for planning, troubleshooting, and communicating network structures.

Key components of a system diagram include devices, network equipment and connections.

Creating a system diagram involves identifying components, arranging them logically & connecting them correctly.