Method and apparatus for handling multicast traffic

• US 9,705,789 B1
• Filed: 02/25/2016
• Issued: 07/11/2017
• 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
• Primary Examiner(s): Kassim, Khaled
• Application Number:
  US15/053,125
• Time in Patent Office: 502 Days
• 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:

learning a topology of a domain to determine broadcast routing trees in the domain by a master node of the domain;

storing, at a first node of the domain, the broadcast routing trees;

forwarding, from the first node to next nodes, a probe message transmitted from a second node in response to a request from a third node;

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

storing, at the first node, a multicast address table including a list of nodes in association with a multicast flow; and

determining the list of nodes based on a snapshot of information of a unicast routing table such that the list of nodes included in the multicast address table does not change when the information in the unicast routing table is updated.

2. The method of claim 1, further comprising:

storing, at the first node of the domain, the unicast routing table including the information to route unicast traffic for transmitting messages in the domain.

3. The method of claim 2, wherein the unicast routing table associates one of the next nodes with the third node.

4. The method of claim 2, wherein the third node joins a group to receive the multicast flow that enters the domain from the second node.

5. The method claim 4, further comprising:

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

6. The method of claim 4, further comprising:

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

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

7. The method of claim 1, wherein forwarding, from the first node to the next nodes, the probe message further comprises:

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

8. The method of claim 7, further comprising:

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

9. An apparatus, comprising:

a controller configured to learn a topology of a domain to determine broadcast routing trees in the domain by a master node of the domain and determine a list of nodes based on a snapshot of information of a unicast routing table such that the list of nodes included in a multicast address table does not change when the information in the unicast routine table is updated;

a memory configured to store, at a first node of the domain, the broadcast routing trees and store, at the first node, the multicast address table including the list of nodes in association with a multicast flow; and

an interface configured to forward, from the first node to next nodes, a probe message transmitted from a second node in response to a request from a third node and receive a path indication message unicasted hop by hop from the third node in a reverse order of a path determined by the third node.

10. The apparatus of claim 9, wherein the memory is further configured to store, at the first node of the domain, the unicast routing table including the information to route unicast traffic for transmitting messages in the domain.

11. The apparatus of claim 10, wherein the unicast routing table associates one of the next nodes with the third node.

12. The apparatus of claim 10, wherein the third node joins a group to receive the multicast flow that enters the domain from the second node.

13. The apparatus of claim 12, wherein the controller is further configured to combine one of the next nodes into the list of nodes in association with the multicast flow.

14. The apparatus of claim 12, wherein the interface is further configured to receive a leave message informing the third node leaving the group and the controller is further configured to update the list of nodes in association with the multicast flow in response to the leave message.

15. The apparatus of claim 9, wherein the interface is further configured to include an identification of the first node in the probe message.

16. The apparatus of claim 15, wherein the interface is further configured to receive the path indication message informing the path determined by the third node based on the identification included in the probe message.