Methods and apparatus for managing multicast groups

• US 8,094,602 B2
• Filed: 08/24/2009
• Issued: 01/10/2012
• Est. Priority Date: 06/26/2007
• Status: Expired due to Fees

• Current Assignee: Media Patents S.L.
• Original Assignee: Media Patents S.L.
• Inventors: Gutierrez, Alvaro Fernandez
• Primary Examiner(s): PARK, JUNG H
• Application Number:
  US12/546,464
• Publication Number:
  US 20090310609A1
• Time in Patent Office: 869 Days
• Field of Search: 370/230, 370/312, 370/389
• US Class Current: 370/312
• CPC Class Codes: H04L 12/185 with management of multicast group membership

Abstract

A method for managing multicast traffic in a data network, and devices using said method. The hosts store for each multicast group an included source record and an excluded source record, and the network interfaces of the hosts send to the router a message containing information about the included source record and information about the excluded source record. The router also stores for each multicast group an included source record and an excluded source record, and updates them when it receives through its network interface a message from the hosts containing information about an included source list and/or information about an excluded source list. The devices are a router, host equipment and network equipment compatible with the method.

Claims

1. A method implemented by a multicast router having one or more downstream network interfaces and situated in a data network system between sources that send multicast packets to at least one multicast group address and one or more hosts that request data from the multicast group address and the sources, the method comprising:

the multicast router storing for a downstream network interface and multicast group address at least one INCLUDE source record containing information about include source lists derived by data requests made by the one or more hosts and at least one EXCLUDE source record containing information about exclude source lists derived by data requests made by the one or more hosts, the multicast router using a host-router multicast routing protocol based on the IGMP (Internet Group Management Protocol) or the MLD (Multicast Listener Discovery) protocol to communicate with the one or more hosts, the multicast router maintaining a source-timer for each of the sources in the include and exclude source lists, the multicast router transmitting for the network interface and each multicast group address multicast packets to the hosts based on the information of the at least one INCLUDE source record and the at least one EXCLUDE source record, the multicast router transmitting for each INCLUDE source of a multicast group address having a source-timer of a value greater than zero multicast packets through the downstream network interface and also transmitting multicast packets of the sources of the multicast group address through the network interface except the EXCLUDE sources having a source timer of a value zero.

2. A method according to claim 1, wherein the multicast router stores for the network interface and multicast group address only one INCLUDE source record and only one EXCLUDE source record.

3. A method according to claim 1, wherein the at least one INCLUDE source record for a downstream network interface and multicast group address comprises (multicast-address, INCLUDE, {source list and timers}) and the at least one EXCLUDE source record comprises (multicast-address, group timer, EXCLUDE, {source list and timers}).

4. A method according to claim 1, wherein the multicast router stores executable instructions for updating the at least one INCLUDE source record and/or the at least one EXCLUDE source record upon receiving a state message or change of state message originating from the one or more of hosts.

5. A method according to claim 1, wherein the multicast router is capable of receiving a state message originating from one or more hosts that includes instructions about the method the multicast router must apply to set up routing trees from the sources to the multicast router.

6. A method according to claim 1, wherein the multicast router stores executable instructions for (1) keeping, for each downstream network interface and multicast group address, at least two separate records:

the INCLUDE source record and the EXCLUDE source record, and (2) updating the INCLUDE source record and the EXCLUDE source record, for each multicast group address, when the multicast router receives, through its downstream network interface, a message containing information about an include source list and information about an exclude source list originating from one or more of the hosts.

7. A method according to claim 1, wherein the multicast router uses a router-router multicast routing protocol to communicate with at least one other multicast router situated between itself and the sources.

8. A method according to claim 7, wherein for a multicast group address the multicast router has an upstream network interface that requests the data from the sources via the at least one other multicast router situated within a routing tree between the sources and the multicast router, the upstream network interface communicates with the at least one other multicast routers via the router-router multicast routing protocol to request the data from the sources using the information in the INCLUDE source record and the information in the EXCLUDE source record to permit connection with the sources through a shortest path tree.

9. A method according to claim 7, wherein the router-router multicast routing protocol is a version of a PIM (Protocol Independent Multicast) protocol.

10. A method according to claim 7, wherein for a multicast group address the multicast router has an upstream network interface that requests the data from the sources via a plurality of multicast routers which include a Rendezvous Point Router, the plurality of multicast routers situated within routing trees between the sources and the multicast router, the routing trees including a rendezvous point tree (RPT) and a shortest path tree (SPT) for the sources, the upstream network interface communicates with the plurality of multicast routers via the router-router multicast routing protocol to request the data from the sources using the information in the INCLUDE source record and the information in the EXCLUDE source record to permit connection with the sources via the shortest path tree without the need to use the rendezvous point tree.

11. A method according to claim 10, wherein the router-router multicast routing protocol is a version of a PIM (Protocol Independent Multicast) protocol.

12. A method according to claim 1, wherein upon receiving in the downstream network interface an IS_IN(x) type message for a multicast group address no EXCLUDE source records for the multicast group address are modified.

13. A method according to claim 1, wherein upon receiving in the downstream network interface an IS_EX(x) type message for a multicast group address no INCLUDE source records for the multicast group address are modified.

14. A method according to claim 1, wherein the multicast router stores executable instructions for 1) receiving messages originating from the one or more hosts requesting the multicast router to stop sending data from a multicast group address and a source;

2) determining whether one or more other hosts are receiving data from the multicast group address and source upon receiving the stop request using the at least one INCLUDE source record and the at least one EXCLUDE source record; and

     3) continuing to send data from the multicast group address and source to the one or more other hosts without sending a group-and-source-specific query type message to the one or more other hosts receiving data from the multicast group address and source.

15. A method implemented by a multicast router having one or more downstream network interfaces and situated in a data network system between sources that send multicast packets to at least one multicast group address and one or more hosts that request data from the multicast group address and the sources, the method comprising:

the multicast router storing for a downstream network interface and multicast group address at least one INCLUDE source record containing information about include source lists derived by data requests made by the one or more hosts and at least one EXCLUDE source record containing information about exclude source lists derived by data requests made by the one or more hosts, the multicast router using a host-router multicast routing protocol based on the IGMP (Internet Group Management Protocol) or the MLD (Multicast Listener Discovery) protocol to communicate with the one or more hosts, the exclude source lists including a requested list and an exclude list, the multicast router transmitting for the downstream network interface and each multicast group address multicast packets to the hosts based on the information of the at least one INCLUDE source record and the at least one EXCLUDE source record.

16. A method according to claim 15, wherein the multicast router maintains a source-timer for each of the sources in the include and exclude source lists.

17. A method according to claim 16, wherein the multicast router transmits for each INCLUDE source of a multicast group address having a source-timer of a value greater than zero multicast packets through the network interface and also transmits multicast packets of the remaining sources of the multicast group address through the network interface except the EXCLUDE sources having a source timer of a value zero.

18. A method according to claim 15, wherein the multicast router uses a router-router multicast routing protocol to communicate with at least one other multicast router situated between itself and the sources.

19. A method according to claim 15, wherein the multicast router stores for the downstream network interface and multicast group address only one INCLUDE source record and only one EXCLUDE source record.

20. A method according to claim 15, wherein the at least one INCLUDE source record for a network interface and multicast group address comprises (multicast-address, INCLUDE, {source list and timers}) and the at least one EXCLUDE source record comprises (multicast-address, group timer, EXCLUDE, {source list and timers}).

21. A method according to claim 15, wherein the multicast router stores executable instructions for updating the at least one INCLUDE source record and/or the at least one EXCLUDE source record upon receiving a state message or change of state message originating from the one or more of hosts.

22. A method according to claim 15, wherein the multicast router is capable of receiving a state message originating from one or more hosts that includes instructions about the method the multicast router must apply to set up routing trees from the sources to the multicast router.

23. A method according to claim 15, wherein the multicast router stores executable instructions for (1) keeping, for each downstream network interface and multicast group address, at least two separate records:

the INCLUDE source record and the EXCLUDE source record, and (2) updating the INCLUDE source record and the EXCLUDE source record, for each multicast group address, when the multicast router receives, through its downstream network interface, a message containing information about an include source list and information about an exclude source list originating from one or more of the hosts.

24. A method according to claim 18, wherein for a multicast group address the multicast router includes an upstream network interface that requests the data from the sources via the at least one other multicast router situated within a routing tree between the sources and the multicast router, the upstream network interface communicates with the at least one other multicast router via the router-router multicast routing protocol to request the data from the sources using the information in the INCLUDE source record and the information in the EXCLUDE source record to permit connection with the sources through a shortest path tree.

25. A method according to claim 18, wherein the router-router multicast routing protocol is a version of a PIM (Protocol Independent Multicast) protocol.

26. A method according to claim 18, wherein for a multicast group address the multicast router includes an upstream network interface that requests the data from the sources via a plurality of multicast routers which include a Rendezvous Point Router, the plurality of multicast routers situated within routing trees between the sources and the multicast router, the routing trees including a rendezvous point tree (RPT) and a shortest path tree (SPT) for the sources, the upstream network interface communicates with the plurality of multicast routers via the router-router multicast routing protocol to request the data from the sources using the information in the INCLUDE source record and the information in the EXCLUDE source record to permit connection with the sources via the shortest path tree without the need to use the rendezvous point tree.

27. A method according to claim 26, wherein the router-router multicast routing protocol is a version of a PIM (Protocol Independent Multicast) protocol.

28. A method according to claim 15, wherein upon receiving in the downstream network interface an IS_IN(x) type message for a multicast group address no EXCLUDE source records for the multicast group address are modified.

29. A method according to claim 15, wherein upon receiving in the downstream network interface an IS_EX(x) type message for a multicast group address no INCLUDE source records for the multicast group address are modified.

30. A method according to claim 15, wherein the multicast router stores executable instructions for 1) receiving messages originating from the one or more hosts requesting the multicast router to stop sending data from a multicast group address and a source;

2) determining whether one or more other hosts are receiving data from the multicast group address and source upon receiving the stop request using the at least one INCLUDE source record and the at least one EXCLUDE source record; and

     3) continuing to send data from the multicast group address and source to the one or more other hosts without sending a group-and-source-specific query type message to the one or more other hosts receiving data from the multicast group address and source.

31. A multicast router for being situated in a data network system between sources that send multicast packets to at least one multicast group address and one or more hosts that request data from the multicast group address and the sources, the multicast router comprising:

one or more downstream network interfaces and storing executable instructions for

     1) communicating with the one or more hosts using a host-router multicast routing protocol based on the IGMP (Internet Group Management Protocol) or the MLD (Multicast Listener Discovery) protocol;

     2) storing for a downstream network interface and multicast group address at least one INCLUDE source record containing information about include source lists derived by the data requests made by the one or more hosts and at least one EXCLUDE source record containing information about exclude source lists derived by the data requests made by the one or more hosts;

     3) maintaining a source-timer for each of the sources in the include and exclude source lists and to transmit for the downstream network interface and each multicast group address multicast packets to the hosts based on the information of the at least one INCLUDE source record and the at least one EXCLUDE source record, and

     4) transmitting for each INCLUDE source of a multicast group address having a source-timer of a value greater than zero multicast packets through the downstream network interface and also transmit multicast packets of the sources of the multicast group address through the downstream network interface except the EXCLUDE sources having a source timer of a value zero.

32. A multicast router according to claim 31, wherein the multicast router stores executable instructions for updating the at least one INCLUDE source record and the at least one EXCLUDE source record upon receiving a state message or change of state message originating from the one or more of hosts.

33. A multicast router according to claim 31, wherein the multicast router stores executable instructions for receiving a state message originating from one or more hosts that includes instructions about the method the multicast router must apply to set up routing trees from the sources to the multicast router.

34. A multicast router according to claim 31, wherein the multicast router stores executable instructions for communicating with at least one other multicast router situated between itself and the sources using a router-router multicast routing protocol.

35. A multicast router according to claim 34, wherein the router-router multicast routing protocol is a version of a PIM (Protocol Independent Multicast) protocol.

36. A multicast router according to claim 31, wherein the multicast router stores executable instructions to cause the multicast router to not modify the EXCLUDE source records for a multicast group address upon receiving in the downstream network interface an IS_IN(x) type message for the multicast group address.

37. A multicast router according to claim 31, wherein the multicast router stores executable instructions to cause the multicast router to not modify the INCLUDE source records for a multicast group address upon receiving in the downstream network interface an IS_EX(x) type message for the multicast group address.

38. A multicast router according to claim 31, wherein the multicast router stores executable instructions to store for the network interface and multicast group address only one INCLUDE source record and only one EXCLUDE source record.

39. A multicast router according to claim 31, wherein the at least one INCLUDE source record for a network interface and multicast group address comprises (multicast-address, INCLUDE, {source list and timers}) and the at least one EXCLUDE source record comprises (multicast-address, group timer, EXCLUDE, {source list and timers}).

40. A multicast router according to claim 31, wherein the multicast router stores executable instructions for 1) receiving messages originating from the one or more hosts requesting the multicast router to stop sending data from a multicast group address and a source;

2) determining whether one or more other hosts are receiving data from the multicast group address and source upon receiving the stop request using the at least one INCLUDE source record and the at least one EXCLUDE source record; and

     3) to continue sending data from the multicast group address and source to the one or more other hosts without sending a group-and-source-specific query type message to the one or more other hosts receiving data from the multicast group address and source.

41. A multicast router for being situated in a data network system between sources that send multicast packets to at least one multicast group address and one or more hosts that request data from the multicast group address and the sources, the multicast router comprising:

one or more downstream network interfaces and storing executable instructions for

     1) communicating with the one or more hosts using a host-router multicast routing protocol based on the IGMP (Internet Group Management Protocol) or the MLD (Multicast Listener Discovery) protocol;

     2) storing for a downstream network interface and multicast group address at least one INCLUDE source record containing information about include source lists derived by the data requests made by the one or more hosts and at least one EXCLUDE source record containing information about exclude source lists derived by the data requests made by the one or more hosts, the exclude source lists including a requested list and an exclude list;

     3) transmitting for the network interface and each multicast group address multicast packets to the hosts based on the information of the at least one INCLUDE source record and the at least one EXCLUDE source record;

     4) maintaining a source-timer for each of the sources in the include and exclude source lists; and

     5) transmitting for each INCLUDE source of a multicast group address having a source-timer of a value greater than zero multicast packets through the downstream network interface and also transmitting multicast packets of the remaining sources of the multicast group address through the downstream network interface except the EXCLUDE sources having a source timer of a value zero.

42. A multicast router according to claim 41, wherein the multicast router stores executable instructions for communicating with at least one other multicast router situated between itself and the sources using a router-router multicast routing protocol.

43. A multicast router according to claim 41, wherein the multicast router stores executable instructions to store for the downstream network interface and multicast group address only one INCLUDE source record and only one EXCLUDE source record.

44. A multicast router according to claim 41, wherein the at least one INCLUDE source record for a network interface and multicast group address comprises (multicast-address, INCLUDE, {source list and timers}) and the at least one EXCLUDE source record comprises (multicast-address, group timer, EXCLUDE, {source list and timers}).

45. A multicast router according to claim 41, wherein the multicast router stores executable instructions for updating the at least one INCLUDE source record and the at least one EXCLUDE source record upon receiving a state message or change of state message originating from the one or more of hosts.

46. A multicast router according to claim 41, wherein the multicast router stores executable instructions for receiving a state message originating from one or more hosts that includes instructions about the method the multicast router must apply to set up routing trees from the sources to the multicast router.

47. A multicast router according to claim 41, wherein the multicast router stores executable to cause the multicast router to not modify the EXCLUDE source records of a multicast group address upon receiving in the downstream network interface an IS_IN(x) type message for the multicast group address.

48. A multicast router according to claim 41, wherein the multicast router stores executable to cause the multicast router to not modify the INCLUDE source records of a multicast group address upon receiving in the downstream network interface an IS_EX(x) type message for a multicast group address.

49. A multicast router for being situated in a data network system between sources that send multicast packets to at least one multicast group address and one or more hosts that request data from the multicast group address and the sources, the multicast router comprising:

one or more downstream network interfaces and storing executable instructions for

     1) communicating with the one or more hosts using a host-router multicast routing protocol based on the IGMP (Internet Group Management Protocol) or the MLD (Multicast Listener Discovery) protocol;

     2) storing for a downstream network interface and multicast group address only one INCLUDE source record containing information about include source lists derived by the data requests made by the one or more hosts and only one EXCLUDE source record containing information about exclude source lists derived by the data requests made by the one or more hosts;

     3) maintaining a source-timer for each of the sources in the include and exclude source lists and to transmit for the downstream network interface and each multicast group address multicast packets to the hosts based on the information of the INCLUDE source record and the EXCLUDE source record, and

     4) transmitting for each INCLUDE source of a multicast group address having a source-timer of a value greater than zero multicast packets through the downstream network interface and also transmit multicast packets of the sources of the multicast group address through the downstream network interface except the EXCLUDE sources having a source timer of a value zero.

50. A multicast router according to claim 49, wherein the multicast router stores executable instructions for updating the INCLUDE source record and the EXCLUDE source record upon receiving a state message or change of state message originating from the one or more of hosts.

51. A multicast router according to claim 49, wherein the multicast router is configured to receive a state message originating from one or more hosts that includes instructions about the method the multicast router must apply to set up routing trees from the sources to the multicast router.

52. A multicast router according to claim 49, wherein the multicast router stores executable instructions for communicating with at least one other multicast router situated between itself and the sources using a router-router multicast routing protocol.

53. A multicast router according to claim 52, wherein the router-router multicast routing protocol is a version of a PIM (Protocol Independent Multicast) protocol.

54. A multicast router according to claim 49, wherein the multicast router stores executable instructions to cause the multicast router to not modify the EXCLUDE source record for a multicast group address upon receiving in the downstream network interface an IS_IN(x) type message for the multicast group address.

55. A multicast router according to claim 49, wherein the multicast router stores executable instructions to cause the multicast router to not modify the INCLUDE source record for a multicast group address upon receiving in the downstream network interface an IS_EX(x) type message for the multicast group address.

56. A multicast router according to claim 49, wherein the INCLUDE source record for a network interface and multicast group address comprises (multicast-address, INCLUDE, {source list and timers}) and the EXCLUDE source record comprises (multicast-address, group timer, EXCLUDE, {source list and timers}).

57. A multicast router according to claim 49, wherein the multicast router stores executable instructions for 1) receiving messages originating from the one or more hosts requesting the multicast router to stop sending data from a multicast group address and a source;

2) determining whether one or more other hosts are receiving data from the multicast group address and source upon receiving the stop request using the INCLUDE source record and the EXCLUDE source record; and

     3) to continue sending data from the multicast group address and source to the one or more other hosts without sending a group-and-source-specific query type message to the one or more other hosts receiving data from the multicast group address and source.

58. A multicast router for being situated in a data network system between sources that send multicast packets to at least one multicast group address and one or more hosts that request data from the multicast group address and the sources, the multicast router comprising:

one or more downstream network interfaces and storing executable instructions for

     1) communicating with the one or more hosts using a host-router multicast routing protocol based on the IGMP (Internet Group Management Protocol) or the MLD (Multicast Listener Discovery) protocol;

     2) storing for a downstream network interface and multicast group address only one INCLUDE source record containing information about include source lists derived by the data requests made by the one or more hosts and only one EXCLUDE source record containing information about exclude source lists derived by the data requests made by the one or more hosts, the exclude source lists including a requested list and an exclude list; and

     3) transmitting for the network interface and each multicast group address multicast packets to the hosts based on the information of the INCLUDE source record and the EXCLUDE source record;

     4) maintaining a source-timer for each of the sources in the include and exclude source lists; and

     5) transmitting for each INCLUDE source of a multicast group address having a source-timer of a value greater than zero multicast packets through the downstream network interface and also transmitting multicast packets of the remaining sources of the multicast group address through the downstream network interface except the EXCLUDE sources having a source timer of a value zero.

59. A multicast router according to claim 58, wherein the multicast router stores executable instructions for communicating with at least one other multicast router situated between itself and the sources using a router-router multicast routing protocol.

60. A multicast router according to claim 58, wherein the INCLUDE source record for a network interface and multicast group address comprises (multicast-address, INCLUDE, {source list and timers}) and the EXCLUDE source record comprises (multicast-address, group timer, EXCLUDE, {source list and timers}).

61. A multicast router according to claim 58, wherein the multicast router stores executable instructions for updating the INCLUDE source record and the EXCLUDE source record upon receiving a state message or change of state message originating from the one or more of hosts.

62. A multicast router according to claim 58, wherein the multicast router stores executable instructions for receiving a state message originating from one or more hosts that includes instructions about the method the multicast router must apply to set up routing trees from the sources to the multicast router.

63. A multicast router according to claim 58, wherein the multicast router stores executable to cause the multicast router to not modify the EXCLUDE source record of a multicast group address upon receiving in the downstream network interface an IS_IN(x) type message for the multicast group address.

64. A multicast router according to claim 58, wherein the multicast router stores executable to cause the multicast router to not modify the INCLUDE source record of a multicast group address upon receiving in the downstream network interface an IS_EX(x) type message for a multicast group address.

65. A multicast router for being situated in a data network system between sources that send multicast packets to at least one multicast group address and one or more hosts that request data from the multicast group address and the sources, the multicast router comprising:

one or more downstream network interfaces and storing executable instructions for

     1) communicating with the one or more hosts using a host-router multicast routing protocol based on the IGMP (Internet Group Management Protocol) or the MLD (Multicast Listener Discovery) protocol;

     2) storing for a downstream network interface and multicast group address at least one INCLUDE source record containing information about include source lists derived by the data requests made by the one or more hosts and at least one EXCLUDE source record containing information about exclude source lists derived by the data requests made by the one or more hosts, the exclude source lists including a requested list and an exclude list;

     3) transmitting for the network interface and each multicast group address multicast packets to the hosts based on the information of the at least one INCLUDE source record and the at least one EXCLUDE source record;

     4) receiving messages originating from the one or more hosts requesting the multicast router to stop sending data from a multicast group address and a source;

     5) determining whether one or more other hosts are receiving data from the multicast group address and source upon receiving the stop request using the at least one INCLUDE source record and the at least one EXCLUDE source record; and

     6) continuing to send data from the multicast group address and source to the one or more other hosts without sending a group-and-source-specific query type message to the one or more other hosts receiving data from the multicast group address and source.

66. A multicast router for being situated in a data network system between sources that send multicast packets to at least one multicast group address and one or more hosts that request data from the multicast group address and the sources, the multicast router comprising:

one or more downstream network interfaces and storing executable instructions for

     1) communicating with the one or more hosts using a host-router multicast routing protocol based on the IGMP (Internet Group Management Protocol) or the MLD (Multicast Listener Discovery) protocol;

     2) storing for a downstream network interface and multicast group address only one INCLUDE source record containing information about include source lists derived by the data requests made by the one or more hosts and only one EXCLUDE source record containing information about exclude source lists derived by the data requests made by the one or more hosts, the exclude source lists including a requested list and an exclude list;

     3) transmitting for the network interface and each multicast group address multicast packets to the hosts based on the information of the INCLUDE source record and the EXCLUDE source record;

     4) receiving messages originating from the one or more hosts requesting the multicast router to stop sending data from a multicast group address and a source;

     5) determining whether one or more other hosts are receiving data from the multicast group address and source upon receiving the stop request using the INCLUDE source record and the EXCLUDE source record; and

     6) continuing to send data from the multicast group address and source to the one or more other hosts without sending a group-and-source-specific query type message to the one or more other hosts receiving data from the multicast group address and source.