Patent ID: 8649375

Claim:
A method of distributing multicast information flows from at least one source to a plurality of user terminals over a network including aggregation routers arranged in hierarchical levels, said hierarchical levels including a last-hop level nearest to said plurality of user terminals, the method including the steps of: receiving a request for an information flow from a user terminal, defining a distribution path having a plurality of said aggregation routers for transmitting said information flow to the user terminal, deriving, by a first of said plurality of aggregation routers used to transmit said information flow at a level of said hierarchical levels other than said last-hop level, an information subflow from said information flow, wherein the information subflow includes a subset of the information included in the information flow, propagating, by said first router, said information flow towards a second of said plurality of aggregation routers used to transmit said information flow and said information subflow towards at least one lower-level aggregation router different from a lower-level router in said plurality of aggregation routers used to transmit said information flow, receiving, at the at least one lower-level aggregation router that received the propagated information subflow, a further request for said information flow, forwarding said further request towards at least one aggregation router that derived said information subflow from said information flow, deriving, by at least two of said plurality of aggregation routers used to transmit said information flow at a level of said hierarchical levels other than said last-hop level including said first router, said information subflow from said information flow, propagating, by said at least two routers, said information subflow towards at least one lower-level aggregation router different from a lower-level router in said plurality of aggregation routers used to transmit said information flow, receiving, by the at least one lower-level aggregation router, said information subflow propagated thereto from said at least two upper-level aggregation routers, and forwarding said further request through the one of said at least two upper-level aggregation routers defining a shorter path to access said information flow.