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Open-source OPC UA client and server library
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nauful Merge pull request #5 from jskala/master
Fixed bug in translating browse paths to node IDs.
Latest commit 0246c95 Oct 27, 2019
Type Name Latest commit message Commit time
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LibUA Fixed bug in translating browse paths to node IDs. Oct 24, 2019
TestClient Initial upload Apr 29, 2019
TestServer Initial upload Apr 29, 2019
LICENSE Initial commit Apr 29, 2019 Update Apr 29, 2019


Open-source OPC UA client and server library for .NET based on IEC 62541. Available as only source files, a demo client and a demo server. Tested and commercially used in industrial applications with commercial vendors' UA servers and clients.


  • Fully supported OPC UA core client and server specification.
  • OPC UA binary protocol with chunking.
  • Optimized memory buffers for encoding/decoding large and complex structures to/from raw bytes.
  • Support for all message types, node types, and default address space from the UA specification.
  • Support for signing and encrypted security profiles.
  • Anonymous, user/pass and certificate-based authentication.
  • Sessions, subscriptions (data change notifications and custom notifications), custom events and alarming.
  • Extendable server address space with hooks for client requests for access control, read handlers, write handlers, etc.
  • Support for reads, writes, updates, historical data and aggregation.
  • Server instances have low overhead: tested with hundreds of clients performing simultaneous historical reads, data change notification subscriptions and real-time writes.


Free for commercial use under the Apache License 2.0. Please give credit if you find this source useful.

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