METHOD AND APPARATUS FOR HANDLING MULTICAST TRAFFIC

• US 20120182991A1
• Filed: 01/13/2012
• Published: 07/19/2012
• Est. Priority Date: 01/13/2011
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Marvell World Trade Limited (Marvell Technology Group Limited)
• Inventors: VAZQUEZ, Marcos Martinez, BADENES CORELLA, Agustin
• Granted Patent: US 9,300,571 B2
• Time in Patent Office: Days
• US Class Current: 370/390
• CPC Class Codes: H04L 12/185 with management of multicast group membership
• CPC Class Codes: H04L 12/1886 with traffic restrictions for efficiency improvement, e.g. involving subnets or subdomains
• CPC Class Codes: H04L 12/2838 Distribution of signals within a home automation network, e.g. involving splitting/multiplexing signals to/from different paths adaptations of television systems for transmission by electric cable for domestic distribution H04N7/106; hybrid transport H04L12/6418; home network arrangements specially adapted for distribution of digital video signals H04N7/24
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 45/26 Route discovery packet
• CPC Class Codes: H04L 45/48 Routing tree calculation
• CPC Class Codes: H04L 45/488 using root node determination

Abstract

Aspects of the disclosure provide method and apparatus for managing multicast traffic in a domain, such as a G.hn domain. A method includes storing, at a first node of a domain, a plurality of next nodes for transmitting messages in the domain, forwarding, from the first node to the plurality of next nodes, a probe message transmitted from a second node in response to a request from a third node to join a group to receive a multicast flow that enters the domain from the second node, and storing, at the first node, a list of nodes in association with the multicast flow. The list of nodes is determined at least in part based on a path through which the probe message is transmitted from the second node to the third node.

Claims

1. A method, comprising:

storing, at a first node of a domain, a plurality of next nodes for transmitting messages in the domain;

forwarding, from the first node to the plurality of next nodes, a probe message transmitted from a second node in response to a request from a third node to join a group to receive a multicast flow that enters the domain from the second node; and

storing, at the first node, a list of nodes in association with the multicast flow, the list of nodes being determined at least in part based on a path through which the probe message is transmitted from the second node to the third node.

2. The method of claim 1, wherein forwarding, from the first node to the plurality of next nodes, the probe message transmitted from the second node in response to the request from the third node to join the group to receive the multicast flow that enters the domain from the second node further comprises:

including an identification of the first node in the probe message.

3. The method of claim 2, further comprising:

receiving a path indication message informing the path determined by the third node based on the included identification in the probe message.

4. The method of claim 3, wherein receiving the path indication message informing the path determined by the third node based on the included identification in the probe message further comprises:

receiving the path indication message unicasted hop by hop from the third node in a reverse order of the path.

5. The method of claim 1, wherein storing, at the first node of the domain, the plurality of next nodes further comprises:

storing, at the first node of the domain, a broadcast routing table that associates the plurality of next nodes with the second node.

6. The method of claim 1, wherein storing, at the first node of the domain, the plurality of next nodes further comprises:

storing, at the first node of the domain, a unicast routing table that associates a next node with the third node.

7. The method of claim 6, further comprising:

combining the next node into the list of nodes in association with the multicast flow.

8. The method of claim 1, further comprising:

receiving a leaving message informing the third node leaving the group; and

updating the list of nodes in association with the multicast flow in response to the leaving message.

9. An apparatus, comprising:

an interface to a transmitting medium, wherein the transmitting medium couples the apparatus as a first node in a domain;

a memory configured to store a plurality of next nodes for transmitting messages in the domain; and

a controller configured to

control the interface to forward, according to the plurality of next nodes, a message transmitted from the second node in response to a request from a third node to join a group to receive a multicast flow that enters the domain from the second node,

determine, at least in part based on a path through which the message is transmitted from the second node to the third node, a list of nodes; and

control the memory to store the list of nodes in association with the multicast flow.

10. The apparatus of claim 9, wherein the controller is configured to include an identification of the first node in the message and control the interface to forward the message.

11. The apparatus of claim 10, wherein the interface receives a path indication message informing the path determined by the third node based on the included identification in the message.

12. The apparatus of claim 11, wherein the interface receives the path indication message unicasted hop by hop from the third node in a reverse order of the path.

13. The apparatus of claim 9, wherein the memory is configured to store a broadcast routing table that associates the plurality of next nodes with the second node.

14. The apparatus of claim 9, wherein the memory is configured to store a unicast routing table that associates a next node with the third node.

15. The apparatus of claim 14, wherein the controller is configured to combine the next node into the list of nodes in association with the multicast flow.

16. The apparatus of claim 9, wherein:

the interface receives a leaving message that the third node leaves the group; and

the controller is configured to update the list of nodes in association with the multicast flow in response to the leaving message.

17. A method, comprising:

storing, at a first node of a domain, a plurality of next nodes;

receiving, at the first node, a request from a second node to join a group to receive a multicast flow that enters the domain from the first node;

initiating and transmitting a probe message in the domain according to the plurality of next nodes; and

storing a list of nodes in association with the multicast flow, the list of nodes being determined at least in part based on a path through which the probe message is transmitted from the first node to the second node.

18. The method of claim 17, further comprising:

unicasting data in the multicast flow to the second node before list of nodes in association with the multicast flow is determined.

19. The method of claim 17, further comprising:

multicasting, according to the list of nodes in association with the multicast flow, data in the multicast flow to the second node after the list of nodes is determined.

20. The method of claim 17, further comprising:

receiving a path indication message informing the path, wherein the path is determined by the second node based on identifications of relay nodes added in the probe message by the relay nodes along the path.

21. The method of claim 20, wherein receiving the path indication message informing the path, further comprises:

receiving the path indication message unicasted hop by hop from the second node in a reverse order of the path.

22. The method of claim 17, further comprising:

receiving a leaving message informing the second node leaving the group for receiving the multicast flow; and

updating the list of nodes in association with the multicast flow in response to the leaving message.

23. The method of claim 17, further comprising:

storing a unicast routing table that associates a next node with the second node; and

combining the next node in the list of nodes in association with the multicast flow.

24. A method, comprising:

sending a join request message from a first node in a domain to join a group to receive a multicast flow;

receiving a probe message transmitted from a second node from which the multicast flow enters the domain, the probe message being transmitted in response to the join request message;

determining a path of the probe message transmitted from the second node to the first node based on identifications of relay nodes added in the probe message by the relay nodes along the path; and

informing the relay nodes of the path.

25. The method of claim 24, further comprising:

receiving data of the multicast flow unicasted from the second node to the first node.

26. The method of claim 24, further comprising:

receiving data of the multicast flow multicasted from the second node to the first node via the relay nodes.

27. The method of claim 24, wherein sending the join request message from the first node in the domain to join the group to receive the multicast flow further comprises:

transmitting the join request message.

28. The method of claim 24, wherein informing the relay nodes of the path further comprises:

unicasting a message including the path hop by hop in a reverse order of the path.

29. The method of claim 24, further comprising:

unicasting a leaving message hop by hop in a reverse order of the path to leave the multicast group.