Each input port of a submodel can either be connected to an input port of the network-model by entries of the optional public section, or it can receive data from the output port of another submodel by defining these connections in the connect section. Otherwise, if neither an input port of the network-model nor the output port of a submodel is connected to a model's port, the port's default setting can be overloaded using the private section. Input ports of multiple submodels may be connected to a single global port as long as their data types are compatible.
The sections public, private, and connect have complementary meanings. This means that if a private section is defined, all ports that are not explicitly treated in that section are automatically defined as public ports, unless they occur in the connect section, and vice versa. If neither the public, nor the private, or the connect section is present, all input ports of a submodel are public by default.