MSDP
Multicast Source Discovery Protocol (MSDP) is a multicast routing protocol belonging to the Protocol Independent Multicast (PIM) family. MSDP interconnects multiple IPv4 PIM Sparse-Mode (PIM-SM) domains, which enables PIM-SM to have Rendez-Vous Point (RP) redundancy and inter-domain multicasting.
Available to all SRX running 12.3X48+
Available to all MX running 20.2R1+
Available to all vSRX running 20.3R1+