A ConformanceUnit represents an individually testable entity. For improved clarity, the large list of ConformanceUnits is arranged into named ConformanceGroups. These groups reflect the Service Sets in OPC 10000-4 and the OPC UA information models. Table 2 lists the ConformanceGroups. These groups and the ConformanceUnits that they describe are detailed in the Subclauses of chapter 5 starting with clause 5.2. ConformanceGroups have no impact on testing; they are used only for organizational reasons, i.e. to simplify the readability of this document.

Table 2 – Conformance Groups



Address Space Model

Defines ConformanceUnits for various features of the OPC UA AddressSpace.


All ConformanceUnits that are related to Aggregates, including individual ConformanceUnits for each supported Aggregate as described in Part 13.

Alarms and Conditions

All ConformanceUnits that are associated with the OPC UA Information Model for Conditions, acknowledgeable Conditions, confirmations and Alarms as specified in Part 9.

Attribute Services

Includes ConformanceUnits to read or write current or historical Attribute values.


User level security includes support for security audit trails, with traceability between Client and Server audit logs.

Base Information

All information elements as defined in Part 5.

Data Access

ConformanceUnits specific to Clients and Servers that deal with the representation and use of automation data as specified in Part 8.

Discovery Services

ConformanceUnits which focus on Server Endpoint Discovery.


Conformance Units for a GDS. Includes units for global discovery and global certificate management.

Historical Access

Access to archived data of Node Attribute values or Events.

Method Services

Methods represent the function calls of Objects. Methods are invoked and return only after completion (successful or unsuccessful).


This group contains ConformanceUnits that cover miscellaneous subjects, such as recommended behaviours, documentation etc. These ConformanceUnits typically do not fit into any of the other groups.

Monitored Item Services

Clients define MonitoredItems to subscribe to data and Events. Each MonitoredItem identifies the item to be monitored and the Subscription to use to send Notifications.

Node Management Services

Bundles ConformanceUnits for all Services to add and delete OPC UA AddressSpace Nodes and References.

Protocol and Encoding

Covers all transport and encoding combinations that are specified in Part 6.


The design of OPC UA ensures that vendors can create redundant Clients and redundant Servers in a consistent manner. Redundancy may be used for high availability, fault tolerance and load balancing.


Security related ConformanceUnits that can be profiled this includes all aspects of security.

Session Services

An (OPC UA) Session is an application layer connection.

Subscription Services

Subscriptions are used to report Notifications to the Client.

View Services

Clients use the View Service Set to navigate through the OPC UA AddressSpace or through a View (a subset) of the OPC UA AddressSpace.