For a fully functioning interface, the other required mechanisms are the communication to the third party system (e.g., calling a specific web service), and performing interface runs (i.e., checking for data to synchronize and doing so if necessary). Fortunately, there is an [[InterfaceAdministration|Interface Administration]] object in {{UBIK}}, that can be used for configuring and triggering interface runs (resulting in an [[InterfaceExecution|Interface Execution]] instance).
Proxies, as any other {{UBIK}} object, require a [[MetaClass ]] describing them. Since proxies have special features, they also have a special MetaClass, called a [[MetaProxy]]. A MetaProxy doesn't just have [[MetaProperty|MetaProperties ]] like a usual MetaClass, but it also has [[ProxyMetaProperty|ProxyMetaProperties]]. These ProxyMetaProperties define interface properties with several interesting details:
* The external system's name of the property
* The Ubikle's (content object's) MetaProperty this ProxyMetaProperty corresponds to