Glossary · System coordination, integration and orchestration
State synchronization
Also known as: State sync
German: Zustandssynchronisierung
In distributed and integrated systems, state synchronization is the process of keeping the state information of a machine, process or object consistent across several systems or components, such as controllers, HMIs, MES and digital twins, so that all of them work with the same view.
- System integration
In one sentence
State synchronization keeps state information consistent across controllers, HMIs, MES or digital twins so all work with the same view.
Example
When an operator acknowledges an alarm on one HMI panel, state synchronization ensures the alarm is shown as acknowledged on all other panels and in the SCADA system.
How it applies
- Engineering: Decide which system is authoritative for each state and how others receive changes: polling, subscriptions or events. Two systems that both write the same state need conflict rules.
- Timing: Consistent timestamps from Time synchronization are needed to order changes from different sources correctly.
- Operation: Out-of-sync states, such as an HMI showing a machine as running when it is stopped, erode operator trust and can cause wrong decisions. Show data quality and staleness.
- Documentation: Document which system owns which state, the update mechanism and the expected delay. Where users might see outdated states, the documentation should say so and explain how to recognize it.
State synchronization vs. state replication
State replication copies the complete state from a primary to replicas, typically for redundancy. State synchronization is broader: it keeps selected state information consistent between different systems that each have their own role.