UDLR-IGMP with Mroute Proxy Operation
2) Router C sends PIM join hop by hop to RP (router B)
3) Router B receives the pim join and adds a
forwarding entry for Group G on LAN B
4) Router B periodically checks its mroute table, and forwards
an IGMP report for each group for which it is the reporter
5) Router A creates and maintains a forwarding entry on the
unidirectional link. Its behavior is the same as with UDLR-IGMP