Communication network topology in SCADA systems - Mini Project: Build & Apply

Communication Network Topology

📖 Scenario: You are working with a SCADA system that monitors and controls industrial processes. The communication network topology defines how devices like sensors, controllers, and servers connect and communicate with each other.Understanding and representing this topology helps in managing the network efficiently and troubleshooting communication issues.

🎯 Goal: Build a simple representation of a communication network topology using a dictionary where each device is a key and its connected devices are listed as values.Then, add a configuration variable to filter devices with more than a certain number of connections.Finally, create a list of devices that meet this connection threshold and display it.

📋 What You'll Learn

Create a dictionary called network_topology with exact device connections

Add a variable called connection_threshold with the value 2

Use a list comprehension to create a list called highly_connected_devices containing devices with connections greater than connection_threshold

Print the highly_connected_devices list

💡 Why This Matters

🌍 Real World

Communication network topologies are essential in SCADA systems to understand how devices connect and communicate, which helps in monitoring and troubleshooting industrial processes.

💼 Career

Knowing how to represent and analyze network topologies is valuable for roles in industrial automation, network administration, and SCADA system maintenance.

1

Create the network topology dictionary

Create a dictionary called network_topology with these exact entries: 'Sensor1': ['Controller1'], 'Sensor2': ['Controller1'], 'Controller1': ['Sensor1', 'Sensor2', 'Server1'], 'Server1': ['Controller1']

SCADA systems

# Create the network_topology dictionary with exact device connections
# Your code here

Hint

Use curly braces {} to create the dictionary and square brackets [] for the lists of connected devices.

2

Add a connection threshold variable

Add a variable called connection_threshold and set it to 2

SCADA systems

network_topology = {
    'Sensor1': ['Controller1'],
    'Sensor2': ['Controller1'],
    'Controller1': ['Sensor1', 'Sensor2', 'Server1'],
    'Server1': ['Controller1']
}
# Add the connection_threshold variable below
# Your code here

Hint

Just assign the number 2 to the variable connection_threshold.

3

Create a list of highly connected devices

Use a list comprehension to create a list called highly_connected_devices that contains devices from network_topology whose number of connections is greater than connection_threshold

SCADA systems

network_topology = {
    'Sensor1': ['Controller1'],
    'Sensor2': ['Controller1'],
    'Controller1': ['Sensor1', 'Sensor2', 'Server1'],
    'Server1': ['Controller1']
}
connection_threshold = 2
# Create the highly_connected_devices list using list comprehension
# Your code here

Hint

Use for device, connections in network_topology.items() and check if len(connections) > connection_threshold.

4

Print the list of highly connected devices

Write a print statement to display the highly_connected_devices list

SCADA systems

network_topology = {
    'Sensor1': ['Controller1'],
    'Sensor2': ['Controller1'],
    'Controller1': ['Sensor1', 'Sensor2', 'Server1'],
    'Server1': ['Controller1']
}
connection_threshold = 2
highly_connected_devices = [device for device, connections in network_topology.items() if len(connections) > connection_threshold]
# Print the highly_connected_devices list below
# Your code here

Hint

Use print(highly_connected_devices) to show the list.

Practice

1. Which communication network topology connects all devices to a single central device?

easy

A. Star topology

B. Ring topology

C. Bus topology

D. Mesh topology

Solution

1. Step 1: Understand the central device role

   In star topology, all devices connect to one central device like a hub or switch.

2. Step 2: Compare with other topologies

   Ring connects devices in a circle, Bus uses a single cable, Mesh connects devices directly to many others.

3. Final Answer:

   Star topology -> Option A

4. Quick Check:

   Central device connection = Star topology [OK]

Hint: Central device means star topology [OK]

Common Mistakes:

• Confusing ring with star because both have connections
• Thinking bus has a central device
• Mixing mesh with star topology

2. Which of the following is the correct way to describe a bus topology?

easy

A. Devices connected to a single communication line

B. Devices connected in a closed loop

C. Devices connected to a central hub

D. Devices connected directly to every other device

Solution

1. Step 1: Define bus topology

   Bus topology connects all devices along a single communication line or cable.

2. Step 2: Eliminate other options

   Closed loop is ring, central hub is star, direct connections to all is mesh.

3. Final Answer:

   Devices connected to a single communication line -> Option A

4. Quick Check:

   Single line connection = Bus topology [OK]

Hint: Bus topology uses one main cable line [OK]

Common Mistakes:

• Confusing ring (closed loop) with bus
• Thinking bus has a central hub
• Mixing mesh with bus topology

3. Given a SCADA network with devices connected so each device links to exactly two others forming a closed loop, what topology is this?

medium

A. Star topology

B. Bus topology

C. Ring topology

D. Tree topology

Solution

1. Step 1: Analyze device connections

   Each device connects to exactly two others forming a closed loop, which matches ring topology.

2. Step 2: Confirm topology type

   Star has central hub, bus is a single line, tree has branches, so ring is correct.

3. Final Answer:

   Ring topology -> Option C

4. Quick Check:

   Closed loop with two neighbors = Ring topology [OK]

Hint: Closed loop with two neighbors means ring topology [OK]

Common Mistakes:

• Choosing star because devices are connected
• Confusing bus with ring
• Thinking tree topology forms a loop

4. A SCADA system uses a mesh topology but experiences frequent communication failures. Which is the most likely cause?

medium

A. Devices connected in a closed loop

B. Single point of failure at central hub

C. Devices connected in a single line

D. Broken link between two devices reduces redundancy

Solution

1. Step 1: Understand mesh topology features

   Mesh topology has multiple connections for redundancy, so a broken link reduces this redundancy.

2. Step 2: Identify failure cause

   Single point failure applies to star, single line is bus, closed loop is ring, so broken link in mesh is likely cause.

3. Final Answer:

   Broken link between two devices reduces redundancy -> Option D

4. Quick Check:

   Mesh failure due to broken link = Broken link between two devices reduces redundancy [OK]

Hint: Mesh fails if links break, losing redundancy [OK]

Common Mistakes:

• Blaming central hub in mesh (no hub exists)
• Confusing bus or ring issues with mesh
• Ignoring link redundancy in mesh

5. You need to design a SCADA communication network that must remain operational even if multiple device connections fail. Which topology best fits this requirement?

hard

A. Bus topology

B. Mesh topology

C. Ring topology

D. Star topology

Solution

1. Step 1: Identify topology with highest fault tolerance

   Mesh topology connects devices with multiple links, so it can handle multiple failures without losing communication.

2. Step 2: Compare other topologies

   Bus fails if main cable breaks, star fails if central hub fails, ring fails if one link breaks.

3. Final Answer:

   Mesh topology -> Option B

4. Quick Check:

   Multiple failure tolerance = Mesh topology [OK]

Hint: Multiple failures? Choose mesh topology [OK]

Common Mistakes:

• Choosing star assuming central hub is fail-safe
• Selecting ring ignoring single link failure risk
• Picking bus despite single cable vulnerability