The OPC Unified Architecture (UA), released in 2008, is a platform independent service-oriented architecture that integrates all the functionality of the individual OPC Classic specifications into one extensible framework.

This multi-layered approach accomplishes the original design specification goals of:

• Functional equivalence: all COM OPC Classic specifications are mapped to UA
• Platform independence: from an embedded micro-controller to cloud-based infrastructure
• Secure: encryption, authentication, and auditing
• Extensible: ability to add new features without affecting existing applications
• Comprehensive information modeling: for defining complex information