Method for updating a multicast state of a multicast group

• US 7,894,378 B2
• Filed: 08/16/2007
• Issued: 02/22/2011
• Est. Priority Date: 08/16/2007
• Status: Active Grant

• Current Assignee: ARRIS Enterprises LLC (CommScope Holding Company, Inc.)
• Original Assignee: Motorola Solutions, Inc.
• Inventors: Zeng, Surong, LEWIS, ADAM C.
• Primary Examiner(s): Pham, Brenda
• Application Number:
  US11/839,735
• Publication Number:
  US 20090046614A1
• Time in Patent Office: 1,286 Days
• Field of Search: 370/310.2, 370/312, 370/328, 370/230, 370/338, 370/349
• US Class Current: 370/312
• CPC Class Codes: H04L 12/185 with management of multicast group membership
• CPC Class Codes: H04L 12/189 in combination with wireless systems selective distribution or broadcast in wireless communication networks H04W4/06
• CPC Class Codes: H04W 4/06 Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]; Services to user groups; One-way selective calling services

Abstract

A method and system for updating a multicast state of a multicast group at a first mesh access point as provided improves network efficiency. According to one aspect, the method includes processing a multicast member join request for the multicast group received from a first wireless node. A proxy update message for the first wireless node received from a third mesh access point is then processed. The first wireless node connects to a second mesh access point after joining the multicast group via the first mesh access point, and the third mesh access point is a root node of a mesh tree of which the second mesh access point is a node. An Internet Group Management Protocol (IGMP) query message for the multicast group is then generated. A multicast update (MUPD) packet is then transmitted to an upstream node, whereby a multicast state is updated at the upstream node.

Claims

1. A method for updating a multicast state of a multicast group, the method comprising:

processing a multicast member join request for the multicast group received from a first wireless node;

processing a proxy update message for the first wireless node received from a third mesh access point, wherein the first wireless node connects to a second mesh access point after joining the multicast group via a first mesh access point, and the third mesh access point is a root node of a mesh tree of which the second mesh access point is a node;

generating an Internet Group Management Protocol (IGMP) query message for the multicast group in response to processing the proxy update message; and

transmitting a multicast update (MUPD) packet to an upstream node in response to determining that an IGMP report for the IGMP query message has not been received from any nodes associated with the first mesh access point, whereby a multicast state is updated at the upstream node.

2. The method of claim 1, further comprising:

determining that an IGMP report for the IGMP query message has not been received from a wireless node; and

updating the multicast state of the multicast group in response to determining that an IGMP report for the IGMP query message has not been received from a wireless node.

3. The method of claim 2, wherein updating the multicast state of the multicast group includes removing a description of the multicast group of which the first and second wireless nodes are members from multicast group information in response to determining that an IGMP report for the IGMP query message has not been received from a wireless node.

4. The method of claim 2, wherein the upstream node is an Intelligent Access Point (IAP).

5. The method of claim 2, wherein the upstream node is the third mesh access point.

6. The method of claim 2, whereby the upstream node removes a description of a mesh multicast tree branch from multicast routing information of the multicast group, wherein the first mesh access point is a node of the mesh multicast tree branch.

7. The method of claim 3, wherein the multicast group information comprises a list of addresses of multicast groups whose members are associated with the first mesh access point.

8. The method of claim 1, wherein the proxy update message is a Proxy Removal (PREM) message.

9. The method of claim 1, wherein the third mesh access point is an Intelligent Access Point (IAP).

10. The method of claim 1, wherein the proxy update message is sent from the third mesh access point in response to the third mesh access point processing a Binding Request (BREQ) message received from the second mesh access point for the first wireless node.

11. The method of claim 10, wherein the BREQ message comprises multicast group information for multicast members associated with the second mesh access point and the following proxy update message generated based on the BREQ also comprises the same multicast group member information.

12. The method of claim 1, wherein the multicast member join request is an Internet Group Management Protocol (IGMP) member join request.

13. The method of claim 1, wherein connections between the first mesh access point and the third mesh access point, and connections between the second mesh access point and the third mesh access point, comprise one or more of wireless connections or wired connections.