These declarations list the interface signals and generic parameters
of the abstract data type components. The source1, queue1, and fork1
components are declared in this slide.
The ports are used to interconnect the elements of the queuing system.
The generics list the static parameters used to configure particular
component instantiations. For example, the queue length is defined as
a generic. The values in the generic lists are default values in case
specific values are not specified when the components are instantiated.
