Object connections are special relations between two logical units where one of the logical units is of general type and may therefore be handled as "public" or "global". Another view of the situation is that common business objects may be connected to general global services in the business area.
These relations/connections can not be seen in the object model of the business classes. Examples of general services are: document connections, project awareness or technical data information.
The difference between object connections and associations is that object connection are dynamic (can be defined in runtime) and don't create dependencies between components.
An object connection server is a logical unit which behaves like a global service to be connected from several other logical units (object connection clients) in a business application. Note that these servers are registered in the presentation layer such as IFS Client Developer (Component.register).
An object connection client is a logical unit whose instances (records) may be connected to some kind of global service (object connection servers). Note that these clients are registered in the server side business logic at install-time (Object_Connection_API.Enable_Connection) and may be changed by tools within IFS/Deployment Administrator.