The ConnectionConfigurationSetType is an ObjectType representing one or more Connection configurations. Connections are grouped in a set, for example, to allow sharing communication model configurations by multiple Connections; see 126.96.36.199.3 and 188.8.131.52.4 for appropriate use cases.
If a ConnectionConfigurationSet is exposed in the AddressSpace, its representation serves two purposes: making Connection configurations available for modification by standard Clients (see Figure 11 label 4) and providing an interface to trigger the processing of such Connection configurations.
- The SelectionListType (see OPC 10000-5) is used to indicate where support for modifications is required by this document. This type allows the generator of the ConnectionConfigurationSet to provide a list of Selections and an optional description of them. It is valid to have Selections with just 1 entry. If the optional RestrictToList is set to TRUE, a Client changing the Variable is restricted to the provided Selections. If set to FALSE or missing, a Client may change the Variable to any value, including one of the Selections. For example, an engineering tool may restrict the PublishingInterval to the values 2 ms, 4 ms, and 8 ms by adding these values to Selections and setting RestrictToList to TRUE.
- Data that has been set to ReadWrite for specific users or in general. This can be determined by examining the AccessLevel and UserAccessLevel Attributes of the data.
With these mechanisms, the generator of the ConnectionConfigurationSet is able to specify and restrict the allowed changes.