Distributed SCADA architecture in SCADA systems - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Key benefit of distributed SCADA systems

Which of the following is the primary advantage of using a distributed SCADA architecture over a centralized one?

A Reduced network traffic by centralizing all control commands

B Lower initial setup cost due to fewer components

C Simplified data management with all data stored in one location

D Improved system reliability by avoiding a single point of failure

💡 Hint

Think about what happens if one part of the system fails in a distributed setup.

Distributed SCADA systems spread control and data processing across multiple nodes. This avoids a single point of failure, improving reliability.

💻 Command Output

intermediate

Output of SCADA node status command

Given a distributed SCADA system with three nodes, what is the expected output of the command `scada-node-status` if node 2 is offline?

SCADA systems

scada-node-status
Node 1: Online
Node 2: Offline
Node 3: Online

A Node 1: Offline\nNode 2: Offline\nNode 3: Offline

B Node 1: Online\nNode 2: Offline\nNode 3: Online

C Node 1: Online\nNode 2: Online\nNode 3: Online

D Error: Unable to retrieve node status

💡 Hint

Check the status of each node individually.

The command lists each node's status. Since node 2 is offline, it shows 'Offline' for node 2 and 'Online' for others.

❓ Configuration

advanced

Configuring redundancy in distributed SCADA

Which configuration snippet correctly sets up a redundant communication link between two SCADA nodes using TCP/IP?

A

link {
  type: tcp
  primary_ip: 192.168.1.10
  port: 502
  redundancy: enabled
}

B

link {
  type: udp
  ip: 192.168.1.10
  port: 502
  redundancy: disabled
}

C

link {
  type: tcp
  primary_ip: 192.168.1.10
  backup_ip: 192.168.1.11
  port: 502
  redundancy: enabled
}

D

link {
  type: tcp
  ip: 192.168.1.10
  port: 502
  redundancy: disabled
}

💡 Hint

Redundancy requires both primary and backup IP addresses.

Option C includes both primary and backup IPs with redundancy enabled, correctly configuring a redundant TCP link.

❓ Troubleshoot

advanced

Diagnosing communication failure in distributed SCADA

A distributed SCADA node cannot communicate with the central server. Which of the following is the most likely cause based on the symptoms: node logs show repeated 'Connection timeout' errors?

A Network firewall blocking TCP port used by SCADA communication

B Central server database corruption

C Node hardware failure causing power loss

D Incorrect SCADA software version installed on the node

💡 Hint

Timeout errors usually relate to network issues.

Connection timeout errors typically indicate network blocks such as firewalls preventing communication on required ports.

🔀 Workflow

expert

Order of steps to deploy a new SCADA node in a distributed system

Arrange the following steps in the correct order to deploy a new SCADA node in a distributed architecture.

A 1,2,3,4

B 2,1,3,4

C 1,3,2,4

D 2,3,1,4

💡 Hint

Think about installing software before configuring network and registering.

The correct workflow is to install software first, then configure network, register the node, and finally test communication.