A system (10), method (90) and apparatus (14) are provided for provisioning a multicast stream, such as an IP multicast stream, in a network. The system includes a first tier (12), such as a national backbone, with a first Multicast Address Discovery (MCAD) directory (34), and at least one second tier having a headend, such as a regional headend (14), with a second MCAD directory (36, 38). The system (10) includes a tiered MCAD directory network that allows the assignment of multicast addresses to multicast streams received from an upper tier MCAD directory. The tiered MCAD directory structure allows for requesting and storing stream descriptors and delivering stream descriptors on-demand to MCAD-enabled devices throughout the system. The system (10) also allows for stream provisioning maintenance and validation at lower tier headends via MCAD-enabled device queries or re-queries of upper tier MCAD directories.