Final answer:
The group-management protocol used in an IPv6-based network for multicast streaming is Multicast Listener Discovery (MLD). It is designed to manage multicast group memberships efficiently, equivalent to IGMP in IPv4 networks.
Step-by-step explanation:
If your multicast streaming AV system runs on an IPv6-based network, the group-management protocol to use is called Multicast Listener Discovery (MLD). MLD is equivalent to Internet Group Management Protocol (IGMP) used for IPv4 but designed specifically for IPv6. It allows IPv6 routers to discover the presence of multicast listeners on their local network and to discover which multicast addresses are of interest to those listeners.
The functioning of MLD is crucial for the efficient delivery of multicast streams. A multicast source can distribute data to multiple receivers through a single transmission only if the network can properly manage the group memberships. Multicast Listener Discovery is part of the suite of network protocols that ensures this management is done effectively, by providing a way for routers to learn which multicast addresses need to be forwarded on each network segment.