A component instance is an instance of a component type. Unlike components, there is no special naming convention for component instances. Drawing a component instance inside a node indicates that the component instance lives or runs on that node during run time.
You can add a component instance to a deployment diagram using the Component tool or the IBM® Rational® Rhapsody® browser.

You can populate a deployment diagram with component instances by dragging them from the Rational Rhapsody browser onto the diagram. The product creates a component instance based on the selected node.