The “Connections” chapter in DataTalk software allows users to establish connections to PLCs, such as Rockwell or MQTT, and serves as a central hub for managing and creating new connections and editing existing ones.

MQTT

MQTT, or Message Queuing Telemetry Transport, is a lightweight and efficient communication protocol commonly used in IoT (Internet of Things) applications. It facilitates communication between devices, following a publish/subscribe or device-to-device model.

In the publish/subscribe model (topic-based), devices can publish messages to a specific “topic.” Other devices subscribe to that topic to receive relevant messages. This decouples the sender and receiver, allowing for efficient and scalable communication.

In the device-based model, communication occurs directly between devices. A unique identifier identifies each device, and messages are exchanged based on these identifiers. This model is suitable for scenarios where a direct connection is preferred or required.

In summary, MQTT provides a flexible and scalable communication framework for IoT applications, supporting topic-based (publish/subscribe) and device-based communication models.

OPC-UA

OPC UA (Unified Architecture) is a communication protocol developed by the OPC Foundation, succeeding the OLE for Process Control (OPC). OPC UA significantly differs from its predecessor by not supporting the older DCOM-based version. The utilization of this protocol offers two primary advantages:

Security: OPC UA establishes secure message interchange through contemporary cryptography, enhancing data protection during communication.

Scalability: The OPC server can effectively communicate with infrastructures from different vendors, promoting interoperability and scalability in industrial automation systems.

It’s important to note that when employing OPC, direct communication with PLCs does not occur. Instead, the OPC server acts as an intermediary, and all communication is contingent on the configuration of the OPC server.

EtherNET/IP

Ethernet/IP is a widely used communication protocol for industrial automation, facilitating seamless communication between Programmable Logic Controllers (PLCs) and Supervisory Control and Data Acquisition (SCADA) systems. This protocol operates over standard Ethernet and is known for its efficiency and versatility in industrial settings. It enables real-time data exchange, device configuration, and control, making it a preferred choice for integrating PLCs with SCADA devices. The use of Ethernet/IP ensures reliable and high-performance communication, enhancing the overall efficiency of industrial processes.

Global / Local Memory

Global / Local memory is a simulated Programmable Logic Controller (PLC) that allows users to simulate and test the functionality of their SCADA system without the need for physical PLC hardware. Users can create and test various data types, develop and optimize control logic, and debug their SCADA applications. This virtual tool provides a user-friendly environment where different scenarios and conditions can be simulated to verify the correctness and reliability of their control system. The Global / Local memory enables users to gain practical experience in PLC and SCADA system programming without the requirement for physical devices.

Rest API

The REST API (Representational State Transfer Application Programming Interface) is a communication protocol used in web services to allow systems to interact with each other over the internet. It is based on the principles of REST architecture and uses standard HTTP methods for communication.

Database

The SQL database communication protocol is a set of rules and methods that allow clients (such as applications) and database servers to communicate with each other and perform database operations.