Legacy Modernization in Industry 4.0

*# [Legacy](/services/legacy modernization)-[modernization](/services/legacy modernization) in Industry 4.0 *

Opened at: 21. January 2026 | Reading time: ca. 10 minutes

table of contents

• Introduction: Where the digital meets the physical world

• Yeah. The challenge: Brownfield environments in production

• Why Legacy Systems Brake Industry 4.0

• modernization strategies for the smart factory

• Application: Predictive Maintenance by Connection of MES Systems

• Conclusion: No Industry 4.0 without IT-modernization

1. Introduction: Where the digital meets the physical world

Industry 4.0 describes the fourth industrial revolution in which the physical world of production merges with the digital world of information technology. Smart factories, the Internet of Things (IoT), artificial intelligence and big data analyses are the drivers of this revolution. However, in many production halls, machines and systems have been used for decades.

These Legacy systems in OT are often isolated, inflexible and not designed for communication in modern IT networks. They form a decisive hurdle on the way to the intelligent factory. This article presents the specific challenges and solutions for the modernisation of legacy systems in the context of Industry 4.0.

Two. The challenge: Brownfield environments in production

In contrast to a "Greenfield" approach where a completely new factory is built on the green meadow, most companies have to follow a "Brownfield" approach. This means that they must gradually modernise and network the existing heterogeneous landscape of old and new machines and systems. Worlds often meet here: the robust OT designed for longevity and the agile, fast-paced IT.

3. Why Legacy Systems Brake Industry 4.0

• Fehlende Connectivity: Old machine controls (SPS) and Manufacturing Execution Systems (MES) often do not have modern interfaces (such as OPC UA or MQTT) to provide data for central analysis.

• Data-Silos: Data are stored in proprietary formats on local systems and are not accessible for higher-level analyses.

• Safety risks: OT systems are often designed for isolated networks and are inadequately protected against cyber attacks when connected to the Internet.

• Inflexibility: The rigid systems cannot be quickly adapted to new production requirements or processes.

4. Modernization strategies for the smart factory

• Edge Computing: Instead of sending all data to the cloud, they are preprocessed by Edge devices directly to the machine. These devices can function as a "translator" between old OT and modern IT and the old systems with new Schnit