View
In OPC UA, a View is the NodeClass that defines a restricted subset of the address space for browsing. A client passes the View's NodeId in a ViewDescription on Browse, and the server returns only the nodes and references that belong to it. Views are rarely implemented in practice.
How a View works
A View node lives under the ViewsFolder at i=87 and adds two attributes: ContainsNoLoops, a hint that the subset is safe to traverse recursively, and EventNotifier, since a View can itself be an event source. Membership is expressed by references from the View node to the nodes it contains. Browsing with an empty ViewDescription, which is what almost every client does by default, means the whole address space.
What Views are for
The intended use is presenting one large address space to different audiences: a maintenance View, a production View, a View containing only the nodes an MES needs. The point is browsing convenience and address-space size reduction, not access control - Views are not a security mechanism, and a node hidden from a View is still readable by NodeId. Part 18 RolePermissions is the mechanism for restricting access.
Reality on the plant floor
Very few servers implement Views, and few clients expose them in their UI. If you need scoped browsing in practice, the working alternatives are Browse filters - ReferenceTypeId, NodeClassMask, ResultMask - type-driven traversal from an ObjectType, or TranslateBrowsePathsToNodeIds against a known model. Treat a View as a nice-to-have you may meet on a large SCADA or aggregating server, not as a design tool you can rely on.
Defined in: Part 3 - Address Space Model, View NodeClass; Part 4 - Services for the ViewDescription parameter of Browse.
Last verified 7 September 2026 against OPC UA 1.05.07. OPC UA Connect is an educational resource and is not affiliated with the OPC Foundation.