# Cognite OPC UA Extractor
The Cognite OPC UA Extractor reads time series, events, and asset information via the open OPC UA protocol. The extractor copies the OPC UA node hierarchy to Cognite Data Fusion (CDF), then streams data and events to time series in CDF.
In this article:
# OPC UA Extractor features
The OPC UA Extractor supports:
- Security using a username/password, or automatically generated client/server certificates.
- Mapping a node hierarchy from an arbitrary root node to CDF.
- Subscribing to data changes in OPC UA and pushing these to destinations.
- Pushing to multiple destinations, currently only InfluxDB databases and CDF.
- Pushing to multiple projects in CDF or multiple InfluxDB databases.
- Reading historical data from OPC UA, starting from the earliest last point found in all push destinations.
- Using properties in OPC UA as metadata in CDF.
- Numerical data types in OPC UA. By default, these are basic types, but you can add additional types in the configuration.
- String values: Non-array data types in OPC UA can be converted to strings and then pushed to CDF.
- Variables in OPC UA with an array-type data type of fixed length can be mapped to multiple different measurements in influx or time series in CDF.
- Setting up a list of events during the configuration. The event properties are automatically mapped and used as metadata in CDF.
- Using different emitters for events than the server node.
- Discovering new nodes through auditing or by periodically re-browsing the node tree.