Monolithic SCADA architecture in SCADA systems - Step-by-Step Execution

Process Flow - Monolithic SCADA architecture

Start SCADA System

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Single Large Application

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Handles Data Collection

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Processes Data

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Manages User Interface

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Controls Devices

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Monolithic SCADA Running

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System Shutdown or Restart

The monolithic SCADA system runs as one big application that collects data, processes it, controls devices, and shows the user interface all together.

Execution Sample

SCADA systems

Start SCADA
Collect Data
Process Data
Control Devices
Show UI
Shutdown

This sequence shows the main steps the monolithic SCADA system performs in order.

Process Table

Step	Action	Component	Result
1	Start SCADA System	Monolithic App	System initializes all modules together
2	Collect Data	Data Collection Module	Reads sensors and gathers data
3	Process Data	Processing Module	Analyzes and prepares data
4	Control Devices	Control Module	Sends commands to devices
5	Show UI	User Interface Module	Displays data and controls to user
6	Shutdown	Monolithic App	Stops all modules and closes system

💡 System stops after shutdown command, all functions end together

Status Tracker

Component	Start	After Step 2	After Step 3	After Step 4	After Step 5	Final
Data Collection	Idle	Active - collecting	Active - data ready	Idle	Idle	Stopped
Processing	Idle	Idle	Active - processing	Idle	Idle	Stopped
Control	Idle	Idle	Idle	Active - controlling	Idle	Stopped
User Interface	Idle	Idle	Idle	Idle	Active - displaying	Stopped

Key Moments - 2 Insights

Why does the whole system stop when one part fails?

Because all parts run inside one big application, a failure in one module can crash the entire system as shown in the execution_table where all components share the same lifecycle.

Can the data collection continue if the UI crashes?

No, in monolithic architecture, all components are tightly connected, so if the UI crashes, the whole system including data collection stops, as seen in the final step of the execution_table.

Visual Quiz - 3 Questions

Look at the execution table, which step activates the Control Module?

A Step 2

B Step 4

C Step 5

D Step 3

💡 Hint

Check the 'Component' and 'Action' columns in the execution_table for when Control Module is active.

At which step does the User Interface Module become active?

A Step 5

B Step 3

C Step 2

D Step 4

💡 Hint

Look at the 'Component' column in the execution_table and find when UI is active.

If the system crashes during data processing, what happens to other modules?

A They keep running independently

B Only UI stops

C All modules stop together

D Only Control stops

💡 Hint

Refer to key_moments and the monolithic nature shown in the execution_table where all modules share the same lifecycle.

Concept Snapshot

Monolithic SCADA architecture runs all functions in one big app.
Data collection, processing, control, and UI are tightly connected.
If one part fails, the whole system stops.
Simple to build but hard to scale or fix parts separately.
Used in small or older SCADA systems.

Full Transcript

Monolithic SCADA architecture means the entire system runs as a single large application. It starts by initializing all modules together. Then it collects data from sensors, processes this data, controls devices, and shows the user interface. All these steps happen inside one big program. If the system shuts down or crashes, all parts stop at once. This design is simple but if one part fails, the whole system stops working. This is because all components share the same lifecycle and resources. Beginners often wonder why one failure affects everything; it is because the system is not split into separate independent parts. This architecture is common in small or older SCADA systems but can be hard to maintain or scale.