Annex A (informative) Design decisions when modelling the server information

A.2 ServerType and Server Object

The first decision is to decide at what level types are needed. Typically, each Server will provide one Server Object with a well-known NodeId. The NodeIds of the containing Nodes are also well-known because their symbolic name is specified in this standard and the NodeId is based on the symbolic name in OPC 10000-6. Nevertheless, aggregating Servers may want to expose the Server Objects of the OPC UA Servers they are aggregating in their AddressSpace. Therefore, it is very helpful to have a type definition for the Server Object. The Server Object is an Object, because it groups a set of Variables and Objects containing information about the Server. The ServerType is a complex ObjectType, because the basic structure of the Server Object should be well-defined. However, the Server Object can be extended by adding Variables and Objects in an appropriate structure of the Server Object or its containing Objects.