CIM_ServiceServiceDependency is an association between a service and another service, indicating that the latter is required ...

CIM_ServiceServiceDependency is an association between a service and another service, indicating that the latter is required to be present, required to have completed, or must be absent for the former service to provide its functionality. For example, boot services may be dependent upon underlying BIOS Disk and initialization services. In the case of the initialization services, the boot service is simply dependent on the init services completing.  For the disk services, boot services may actually utilize the SAPs of this service.  This usage dependency is modeled via the CIM_ServiceSAPDependency association.