Patent ID: 7830787

Claim:
A method for multicast transmission comprising: sending a multicast data stream on a multicast distribution tunnel (MDT)-default tunnel, wherein the MDT-default tunnel is a point-to-multipoint tunnel from a source provider edge router to a first plurality of provider edge routers, and the MDT-default tunnel transmits an additional multicast data stream other than the multicast data stream; detecting that the multicast data stream has exceeded a specified bandwidth; switching the multicast data stream to an MDT-data tunnel in response to the detecting wherein the MDT-data tunnel is a point-to-multipoint tunnel from the source provider edge router to a second plurality of provider edge routers, said second plurality is a proper subset of said first plurality when the switch occurs, each of said second plurality of provider edge routers joins a group in response to the group being advertised by the source provider edge router prior to said switching, said MDT-data tunnel transmits only the multicast data stream, and said switching comprises stopping transmission of the multicast data stream via the MDT-default tunnel, and subsequent to said stopping, beginning transmission of the multicast data stream via the MDT-data tunnel; and switching the multicast data stream back to the MDT-default tunnel if both said flooding conditions cease and the time since the multicast data stream was switched to the MDT-data tunnel has exceeded a specified wait time.