Which difference should be considered when intradomain or interdomain multicast routing is implemented?

Interdomain multicast routing requires an IS-IS or OSPF neighbor relationship between the domains but intradomain multicast routing requires only BGP

Interdomain multicast routing relies on PIM-DM and intradomain multicast routing relies on PIM-SM.

interdomain multicast routing uses BIDR-PIM to establish neighbor relationships between AS and interdomain multicast routing uses MSDP

A network uses intradomain multicast routing without interdomain routing but networks that use interdomain multicast routing must also apply intradomain routing