Components
A component is the basic element of business function. It is defined at design time.
Components are configured instances of implementations. More than one component can use and configure the same implementation.
Components can have services, references, and properties. All of these can be promoted to the composite level during design time. Promotion enables an Administrator to wire or configure services, references, and properties when the application is deployed. Services, references, and properties that are not promoted are private to the application and are set at design time only.
Components can have several different types of dependencies. Components can express dependencies on product features, custom features, other components, and resources. All of a component's dependencies must be satisfied for it to be deployed to a node.
Components can be deployed to multiple nodes for fault tolerance or load balancing.