Because z/VM® Guest Coupling Simulation Support simulates a real coupling facility, the software must create a unique Node Descriptor (ND) for every CF Service Machine to be used. z/VM dynamically creates an architecturally correct unique ND when the message facility environment is created in the CF Service Machine. The method used to create the DN is documented so that the user can generate the administrative policy for CFRM in MVS™. This will allow MVS's CFRM policy generator to be used and there is no need for the user to specify an ND. This is exactly how it works with the real hardware.