300+ SCADA Protocol Articles & Guides
Deep dives on Modbus, DNP3, IEC 60870-5-101/104, IEC 61850, OPC UA, Profinet, MQTT, IEC 62443, and substation automation — written for practicing engineers.
DNP3 Port Number Explained: TCP/UDP 20000, Secure Port 19999, and Firewall Configuration
Learn about the DNP3 port 20000 — its purpose, configuration, security measures, and best practices for safe SCADA communication in industrial networks.
DNP3 Report by Exception, Background Polls, and Balanced Communication
Explore DNP3’s report by exception mode, periodic background polls, and balanced communication that improve SCADA efficiency and reliability.
Modbus over RS485 Communication Frequency and Baud Rate
Modbus over RS485 communication frequency explained: real baud rate limits, bit timing, cable length, and how to size your poll cycle correctly in the field.
DNP3 System Topology Explained: Master, Multidrop, and Hierarchical
Learn about DNP3 system topologies — master–slave, multidrop, hierarchical, and multiple-master — used in SCADA communication networks.
Link Initialization in IEC 60870-5-101 | Master-Slave Communication Setup
Learn how link initialization works in IEC 60870-5-101. Understand master-slave setup, balanced links, and reliable SCADA startup procedures.
IEC 101 Frame Formats Explained | Fixed & Variable Frames
Learn IEC 101 frame formats. Understand fixed and variable-length frames, control fields, and ASDU structure with real IEC 101 examples.
DNP3 Message Structure Explained
Explore how DNP3 messages are structured across layers — from APDU to CRC frames — ensuring reliable and secure SCADA communication.
DNP3 Secure Authentication Version 5 (SAv5): Strengthening SCADA Communication Security
Learn how DNP3 Secure Authentication (SAv5, IEEE 1815-2012) protects SCADA systems using cryptographic challenge–response verification and message integrity checks.
IEC-101 vs IEC-104 — Key Differences Explained
Clear technical comparison of IEC-101 vs IEC-104, explaining key differences, communication flow, and how IEC-101 to IEC-104 conversion works.
Originator Address in IEC 60870-5-101 Explained
Learn how the originator address works in IEC 60870-5-101. Understand its role in multi-master SCADA networks, dual-mode stations, and message routing.
DNP3 IIN (Internal Indications) Bits Meaning & SCADA Troubleshooting Guide
Learn what DNP3 IIN bits are, how they work, and how to decode internal indications in SCADA systems for reliability, event handling, and cybersecurity monitoring.
Wireshark IEC 104: Decode IEC 60870-5-104 Traffic
Wireshark IEC 104 decoding on TCP 2404: I, S, and U frame types, ASDU type IDs, cause of transmission values, CP56Time2a timestamps, and SPAN capture setup.
How IEC 60870-5-104 Works Over Ethernet — Complete Technical Guide
Learn how IEC 60870-5-104 transmits SCADA data over Ethernet and TCP/IP, including frame structure, connection flow, and real-world implementation tips.
IEC 60870-5-104 Time Synchronization (CP56Time2a) — Complete Technical Guide
Learn how IEC 60870-5-104 uses CP56Time2a for precise SCADA time synchronization, timestamping, and event accuracy across control systems.
Adjusting Timeout Values (t0–t3) in IEC 60870-5-104 — Complete Guide
Learn how to configure and fine-tune IEC 60870-5-104 timeout values t0–t3 for reliable SCADA communication and link supervision.
Zero-Trust Architecture for SCADA — Securing IEC 60870-5-104 Systems
Adopt Zero-Trust Architecture for SCADA and IEC 60870-5-104 systems to secure networks, authenticate devices, and prevent insider and external threats.
RS232 vs RS485: Key Differences, Comparison, and Pinout Explained
Compare RS232 vs RS485 communication standards — learn key differences in wiring, pinouts, speed, distance, and applications for serial devices.
Balanced and Unbalanced Transmission in IEC 60870-5-101
Explore the differences between balanced and unbalanced transmission in IEC 60870-5, key features, advantages, and applications in SCADA communication systems.