Category Archives: Communication Protocols

OPC UA Architecture Explained: Complete IEC 62541 Architecture Guide

The OPC Unified Architecture (OPC UA) defines a platform-independent, service-oriented architecture for secure and reliable data exchange in industrial automation systems. The architectural concepts of OPC UA are standardized in the IEC 62541 series, which specifies the communication models, information modeling framework, services, and security mechanisms used to implement interoperable industrial communication systems. Unlike legacy OPC specifications that… Read More »

What Is OPC UA Protocol? Architecture, Security, Address Space and IEC 62541 Guide

Modern industrial systems require reliable, secure, and vendor-independent communication between controllers, sensors, SCADA platforms, historians, and enterprise systems. Traditional industrial protocols were often designed for specific vendors or platforms, which created interoperability limitations. The OPC UA protocol (Open Platform Communications Unified Architecture) solves this challenge by providing a standardized, secure, and platform-independent communication framework for industrial automation systems.… Read More »

IEC 61158 Parts 5 & 6 Explained: Application Layer & Protocol Machines

The application layer is where industrial communication becomes meaningful. If: Then the application layer defines what those frames actually mean. IEC 61158 Parts 5 and 6 define: This layer enables: This article explains the IEC 61158 application layer in clear, practical terms for automation engineers and protocol developers. 1. What the Application Layer Does The application layer (Layer… Read More »

IEC 61158 Data-Link Layer Guide (Parts 3 & 4 Explained)

The data-link layer is where deterministic industrial communication truly begins. If: Then IEC 61158 Parts 3 and 4 define how frames are structured, timed, and controlled. The data-link layer: This article explains the IEC 61158 data-link layer in practical engineering terms. 1. What the Data-Link Layer Does The data-link layer (Layer 2 of OSI) is responsible for: It… Read More »

IEC 61158-2 Physical Layer Explained: Media, Signaling & Deterministic Communication

IEC 61158-2 defines the physical layer specification for industrial fieldbus communication systems. It establishes the electrical, optical, and timing rules that allow deterministic data transmission between industrial devices. While IEC 61158-1 defines the architecture of the standard,IEC 61158-2 defines how bits physically travel across copper and fiber media. This article explains the IEC 61158-2 physical layer in clear,… Read More »

IEC 61158 Explained: Fieldbus Standard Architecture & OSI Model Guide

If you work in industrial automation, PLC integration, or SCADA system design, you will eventually encounter IEC 61158. But IEC 61158 is not a single protocol. It is a family of international standards that define how industrial fieldbus communication systems are structured — from the physical wiring all the way up to the application layer. This article explains… Read More »

Modbus Troubleshooting in SCADA — 15 Real Field Problems Engineers Face

Modbus is simple, but real SCADA integration is rarely simple. In power systems, automation, and industrial plants, most commissioning delays come from small configuration mistakes or physical-layer issues — not from the protocol itself. This guide explains 15 real Modbus problems engineers face on site, how to recognize them quickly, and what practical actions solve them. The explanations… Read More »

IEC 61850-3 Ethernet Switch: Requirements & Substation Use

Ethernet has become the backbone of modern power system automation. From protection relays and bay controllers to SCADA gateways and digital substations, Ethernet networks now carry time-critical protection traffic alongside operational and engineering data. However, substations are among the harshest environments in which communication equipment can be installed. High electromagnetic interference, wide temperature ranges, vibration, and electrical transients… Read More »

IEC 61850 MMS Port Number Explained: Why TCP Port 102 Is Used

IEC 61850 has become the global standard for substation communication systems, enabling interoperability between protection relays, bay controllers, SCADA systems, and engineering tools. At the heart of IEC 61850 client/server communication is MMS (Manufacturing Message Specification)—and one of the most searched questions is: What port number does IEC 61850 MMS use? This article provides a complete explanation of… Read More »

IEC 60870-5-104 Port Numbers Explained: TCP 2404 & Secure TLS Port 19998

IEC 60870-5-104, commonly called IEC 104, is a widely used communication protocol in power system SCADA networks. Because IEC 104 runs over TCP/IP, port numbers are a critical part of how devices communicate, how firewalls are configured, and how cybersecurity is enforced. This guide explains all IEC 60870-5-104 port numbers, with a clear focus on unsecured connections using… Read More »