An instance node of a network represents an instance of another network. In other words, an instance node represents a sub-network. A network containing one or more instance nodes is to be considered an object-oriented network. An instance node is created using the Instance Tool. In order for an instance node to be connected to other (basic) nodes, the network class of which it is an instance must contain interface nodes (i.e., input nodes and/or output nodes).
An instance node is displayed as a rounded rectangle containing the interface nodes of the instance that it represents. See Figure 1 for an example.