Concepts
This section explains how the gateway works and the words the rest of the documentation uses. Read it before configuring a gateway or building on its API; each page stands on its own, so you can also come back to one when a term in another section is unclear.
| Page | What it covers |
|---|---|
| Architecture | Core and modules, the NATS JetStream event backbone, SQLite, the path a value takes from a source to subscribers, alarms and the historian, the module boundary, script workers, secrets at rest, and what runs in the container |
| Tags | What a tag is, the tag kinds and where each gets its value, quality and timestamps, scaling and deadband, writes and the audit trail, and the tag browser in the dashboard |
| Tag types | Tag types (UDTs): parameters, members and nested types, placeholder substitution, instances and overrides, inheritance, tags added to an instance, the built-in types and alarm templates |
| Alarms | Alarm definitions and conditions, states and acknowledgement, how quality affects evaluation, alarm history and live frames |
| History and replay | Where history comes from, the historian and the backbone fallback, checkpoints, and replaying the plant as it was to one connection |
| Security | Roles, sessions and API keys, trusted origins, identity providers, and what is audited |
A few terms used throughout: the gateway is the server; the dashboard is its web UI, served by the gateway itself; a module is an optional component loaded into the gateway, and a driver is a module that connects to a device or broker; a connection is a configured device or broker inside a driver; a tag type is what the API calls a UDT, and an instance is one tag built from it. The glossary has the full list.