OPC UA is a platform-independent standard that enables various systems and devices to communicate securely and reliably. It employs mechanisms for authentication, encryption, and integrity checks to ensure the identity of OPC UA Applications as well as identification of users and protect against attacks.

Using the ClientServer model, OPC UA defines sets of Services that Servers provide, and it utilizes both OPC UA-defined and vendor-defined data types, along with flexible object models, to facilitate interoperability and dynamic information discovery by Clients. Supporting a variety of communication protocols and data encodings, such as TCP, HTTPS, WebSockets, XML/text, UA Binary, and JSON, OPC UA allows for trade-offs between portability and efficiency to suit different application requirements. Servers can provide access to both current and historical data, as well as Alarms and Events to notify Clients of important changes.

In addition to the ClientServer model, OPC UA also supports information transfer from Publishers to Subscribers using the PubSub model.