Active multicast information protocol

• US 20060159092A1
• Filed: 01/28/2005
• Published: 07/20/2006
• Est. Priority Date: 01/19/2005
• Status: Active Grant

• Current Assignee: Arjen Boers, Ijsbrand Wijnands
• Original Assignee: Arjen Boers, Ijsbrand Wijnands
• Inventors: Boers, Arjen, Wijnands, Ijsbrand
• Granted Patent: US 8,243,643 B2
• Time in Patent Office: Days
• US Class Current: 370/390
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 45/28 using route fault recovery

Abstract

In the disclosed active multicast information protocol, a first edge router of a network receives a data packet from a source, wherein the data packet comprises data to be sent to receivers of a multicast group. The first edge router may rout the data packet to a first core router within the network. The first edge router also generates a message in response to receiving the data packet. This message is transmitted to the first core router within a network. The message includes an address of the source, but the message lacks data to be transmitted to the receivers of the multicast group. Another edge router stores the first multicast group and source addresses in an entry of a look-up table (LUT) in response to the edge router receiving a first message directly or indirectly from the first edge router.

Claims

1-37. -37. (canceled)

38. A memory medium configured to store instructions executable by one or more processors in an edge router, wherein the one or more processors are configured to perform a method in response to executing the instructions, the method comprising an act of storing first multicast group and source addresses in an entry of a look-up table (LUT) in response to the edge router receiving a first message directly or indirectly from another edge router, wherein the first message comprises the first multicast group and source addresses, wherein the first source address identifies a first source that transmits data to receivers corresponding to the first multicast group address.

39. The memory medium of claim 38 wherein the method further comprises an act of storing second multicast group and source addresses in another entry of the LUT in response to the edge router receiving a second message directly or indirectly from a third edge router, wherein the second message comprises the second multicast group and source addresses, wherein the second source address identifies a second source that transmits data to receivers corresponding to the second multicast group address.

40. The memory medium of claim 38 wherein the method further comprises:

reading the first source address from the LUT in response to the edge router receiving a first IGMP membership report from a first device, wherein the first IGMP membership report comprises the first multicast group address;

generating a first PIM request to join the first multicast group in response to reading the first source address from the LUT, wherein the first PIM request to join comprises the first source address read from the LUT.

41. The memory medium of claim 38 wherein the method further comprises:

reading the first source address from the LUT in response to the edge router receiving a first IGMP membership report from a first device, wherein the first IGMP membership report comprises the first multicast group address;

initiating a creation of a source specific multicast tree to the first source corresponding to the first source address read from the LUT.

42. The memory medium of claim 40 wherein the first PIM request to join further comprises the first multicast group address and the first source address.

43. The memory medium of claim 38 wherein the LUT is stored in memory within the edge router.

44. The memory medium of claim 39 wherein the method further comprises:

receiving a second IGMP membership report from a second device, wherein the second IGMP report comprises the second multicast group address;

accessing the LUT using the second multicast group address;

the LUT returning the second source address in response to the second edge router accessing the table using the second multicast group address;

generating and transmitting a second PIM request to join the second multicast group identified by the second multicast group address in response to the table returning the second source address;

wherein the second PIM request comprises the addresses of the second multicast group and the source.

45. The memory medium of claim 38 wherein the method further comprises an act of removing or invalidating the entry from the LUT after the first source stops transmitting data to receivers of the first multicast group.

46. The memory medium of claim 38 wherein the method further comprises an act of removing or invalidating the entry from the LUT a period of time after the valid entry is created in the table, wherein the period of time is defined by a hold time value contained in the first message.

47. The memory medium of claim 38 wherein the method further comprises an act of removing or invalidating the entry from the LUT after the source stops transmitting data to receivers of the first multicast group.

48. The memory medium of claim 38 wherein the first message further comprises a data transmission rate value, wherein the data transmission rate value defines a rate at which the first source transmits data to receivers of the first multicast group.

49. A method comprising:

an edge router storing first multicast group and source addresses in an entry of a look-up table (LUT) in response to the edge router receiving a first message directly or indirectly from another edge router;

wherein the first message comprises the first multicast group and source addresses, wherein the first source address identifies a first source that transmits data to receivers corresponding to the first multicast group address.

50. The method of claim 49 further comprising:

the edge router storing second multicast group and source addresses in another entry of the LUT in response to the edge router receiving a second message directly or indirectly from a third edge router;

wherein the second message comprises the second multicast group and source addresses, wherein the second source address identifies a second source that transmits data to receivers corresponding to the second multicast group.

51. The method of claim 49 further comprising:

the edge router reading the first source address from the LUT entry in response to the edge router receiving a first IGMP membership report from a first device, wherein the first IGMP membership report comprises the first multicast group address;

the edge router generating a first PIM request to join the first multicast group in response to reading the first source address from the LUT entry.

52. The method of claim 49 further comprising:

the edge router reading the first source address from the LUT entry in response to the edge router receiving a first IGMP membership report from a first device, wherein the first IGMP membership report comprises the first multicast group address;

the edge router initiating a creation of a source specific multicast tree to the first source identified by the first source address read from the LUT entry.

53. The method of claim 51 wherein the PIM request to join further comprises the first multicast group address and the first source address.

54. The method of claim 50 further comprising:

receiving a second IGMP membership report from a second device, wherein the second IGMP report comprises the second multicast group address;

accessing the LUT using the address of the second multicast group;

the LUT returning the second source address in response to the second edge router accessing the table using the second multicast group address;

generating and transmitting a second PIM request to join the second multicast group identified by the second multicast group address in response to the table returning the address of the second source;

wherein the second PIM request comprises the addresses of the second multicast group and the source.

55. The method of claim 49 further comprising an act of removing or invalidating the entry from the LUT after the first source stops transmitting data to receivers of the first multicast group.

56. The method of claim 49 further comprising an act of removing or invalidating the entry from the LUT a period of time after the valid entry is created in the LUT, wherein the period of time is defined by a hold time value contained in the first message.

57. The method of claim 49 further comprising an act of removing or invalidating the entry from the LUT after the first source stops transmitting data to receivers of the first multicast group.

58. The method of claim 49 wherein the first message further comprises a data transmission rate value, wherein the data transmission rate value defines a rate at which the first source transmits data to receivers of the first multicast group.

59. An apparatus comprising:

an edge router coupled to an SM network and a device;

wherein the edge router comprises one or more microprocessors and a memory for storing instructions executable by the one or more processors, wherein the one or more processors implement a method in response to executing the instructions, the method comprising;

storing first multicast group and source addresses in an entry of a look-up table (LUT) in response to the edge router receiving a first message directly or indirectly from another edge router;

wherein the first message comprises the first multicast group and source addresses, wherein the first source address identifies a first source that transmits data to receivers corresponding to the first multicast group address.

60. The method of claim 59 further comprising:

the edge router reading the first source address from the LUT entry in response to the edge router receiving a first IGMP membership report from a first device, wherein the first IGMP membership report comprises the address of the first multicast group;

the edge router generating a PIM request to join the first multicast group in response to reading the address of the first source from the LUT entry.

61. The method of claim 59 further comprising:

the edge router reading the address of the first source from the LUT entry in response to the edge router receiving a first IGMP membership report from a first device, wherein the first IGMP membership report comprises the address of the first multicast group;

the edge router initiating a creation of a source specific multicast tree to the first source identified by the first source address read from the LUT entry.

62. The method of claim 60 wherein the PIM request to join further comprises the first multicast group address and the first source address.

63. The method of claim 59 further comprising:

receiving a second IGMP membership report from a second device, wherein the second IGMP report comprises a second multicast group address;

accessing the LUT using the address of the second multicast group;

the LUT returning an address of a second source in response to the second edge router accessing the LUT using the second multicast group address;

generating and transmitting a second PIM request to join the second multicast group identified by the second multicast group address in response to the table returning the address of the second source;

wherein the second PIM request comprises the addresses of the second multicast group and the second source.

64. The method of claim 59 further comprising an act of removing or invalidating the entry from the table after the first source stops transmitting data to receivers of the first multicast group.

65. The method of claim 59 further comprising an act of removing or invalidating the entry from the LUT a period of time after the valid entry is created in the table, wherein the period of time is defined by a hold time value contained in the first message.

66. The method of claim 59 further comprising an act of removing or invalidating the entry from the LUT after the first source stops transmitting data to receivers of the first multicast group.

67. An apparatus comprising:

an edge router coupled to a SM network and a device;

means for storing first multicast group and source addresses in an entry of a look-up table (LUT) in response to the edge router receiving a first message directly or indirectly from another edge router;

wherein the first message comprises the first multicast group and source addresses, wherein the first source address identifies a first source that transmits data to receivers corresponding to the first multicast group address.

68-69. -69. (canceled)