  The CDF detector simulation framework is integrated into an AC++ application
used to process events in the CDF experiment. The simulation framework is based
on the GEANT3 package. It holds the detector element geometry descriptions,
allows configuration of digitizers at run-time and manages the generated data.
The design is based on generic programming which allows for easy extension of
the simulation framework. The overall design, details of specific detector
components and in particular the performance of the CDF simulation compared to
collider data are described.
