PimReg DR Filtering provides the ability to prevent unauthorized unicast addresses from registering with a rendezvous-point (RP) router.  This is accomplished by adding the unauthorized unicast address to a standard access-list. When the ACL is used on the RP, the RP inspects the source information on the PIM Register packet for a match before accepting/dropping the message. 

PIM Static Source Discovery (SSD) is a feature implemented as part of PIM-SM. Familiarity with setting up and configuring PIM-SM (Sparse Mode) and PIM-SSM (Source-Specific Multicast) is assumed.