CCST Communications & Networking in Control Systems Flashcards
6 cards from real CCST practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 CCST Communications & Networking in Control Systems flashcards as text
In a DCS (Distributed Control System), what is the primary function of the communication highway or control bus?
Answer: To transfer process data and control signals between controllers and I/O modules in real time
The DCS control bus is the high-speed, deterministic backbone that carries process variable data and control outputs between the controller, I/O subsystems, and operator stations.
What does the acronym OPC-UA stand for in the context of industrial automation data exchange?
Answer: Open Platform Communications – Unified Architecture
OPC-UA (Open Platform Communications Unified Architecture) is a platform-independent, service-oriented architecture for secure and reliable data exchange in industrial automation.
Which wireless standard is most commonly used for low-power, mesh-networked industrial sensors operating in the 2.4 GHz band?
Answer: ZigBee (IEEE 802.15.4)
ZigBee, based on IEEE 802.15.4, is designed for low-power, low-data-rate mesh networks commonly used for industrial sensor networks in the 2.4 GHz band.
A CCST technician is asked to verify network cable integrity on a PROFIBUS DP segment. Which test instrument would best identify impedance mismatches and cable breaks?
Answer: Time Domain Reflectometer (TDR)
A TDR sends a signal pulse down the cable and measures reflected signals to pinpoint cable breaks, shorts, and impedance mismatches with distance accuracy.
In industrial cybersecurity, what does the concept of 'defense in depth' applied to a control network primarily involve?
Answer: Implementing multiple overlapping layers of security controls so no single failure compromises the system
Defense in depth uses multiple, overlapping security layers (firewalls, DMZs, authentication, patching) so that a breach of one layer does not expose the entire control system.
What is the recommended network architecture per ISA/IEC 62443 to separate the business IT network from the industrial control system (ICS) network?
Answer: A DMZ (Demilitarized Zone) with firewalls on both sides between the IT and OT networks
ISA/IEC 62443 recommends a DMZ with dual firewalls to create a buffer zone between IT and OT networks, preventing direct access from business systems to control systems.