Synchronization of multicast information using bicasting

• US 8,576,703 B2
• Filed: 10/27/2010
• Issued: 11/05/2013
• Est. Priority Date: 03/19/2010
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Brocade Communications Systems, Inc. (Broadcom, Inc.)
• Inventors: Dholakia, Mehul, Yeung, Wing-Keung Adam, Pudiyapura, Ajeer S.
• Primary Examiner(s): HSU, ALPUS
• Application Number:
  US12/913,598
• Publication Number:
  US 20110228771A1
• Time in Patent Office: 1,105 Days
• Field of Search: 370/220, 370/312, 370/390, 370/432, 455/445, 709/208, 709/220, 709/230, 709/238, 714/4.11
• US Class Current: 370/220
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 45/16 Multipoint routing
• CPC Class Codes: H04L 45/586 of virtual routers
• CPC Class Codes: H04L 49/201 Multicast operation; Broadcast operation
• CPC Class Codes: H04L 49/354 for supporting virtual local area networks [VLAN]

Abstract

Techniques that enable a network device such as a router to provide multicast routing services without interruption. Techniques are provided for using bicasting to synchronize multicast information maintained by a first processor and multicast information maintained by a second processor. A multicast protocol related event of packet is sent to both a first processor operating in active mode and a second processor operating in standby mode. Each processor then updates its multicast information based upon the bicasted event or packet.

Claims

1. A method comprising:

selectively bicasting a multicast protocol-related packet, received at a processing component of a network device, to a first processor and a second processor based upon a multicast protocol-related packet type, wherein selectively bicasting comprises;

upon determining the multicast protocol-related packet to be of a first type,

sending, from the processing component, a copy of the multicast protocol-related packet to the first processor operating in active mode, the first processor performing a set of multicast routing-related functions in the active mode, and

sending, from the processing component, a copy of the multicast protocol-related packet to the second processor operating in standby mode, the second processor not performing the set of multicast routing-related functions in the standby mode;

updating, by the first processor, first multicast information maintained by the first processor based upon the copy of the multicast protocol-related packet received by the first processor; and

updating, by the second processor, second multicast information maintained by the second processor based upon the copy of the multicast protocol-related packet received by the second processor.

2. The method of claim 1 wherein the multicast protocol-related packet is a Protocol Independent Multicast (PIM) packet.

3. The method of claim 2 wherein the first multicast information updated by the first processor comprises information related to neighbors of the network device that support PIM protocol.

4. The method of claim 1 wherein the multicast protocol-related packet is an Internet Group Membership Protocol (IGMP) packet.

5. The method of claim 4 wherein the first multicast information updated by the first processor comprises information related to the IGMP.

6. The method of claim 1 further comprising:

communicating update information from the first processor to the second processor, the update information comprising information indicative of a change made to the first multicast information; and

updating the second multicast information based upon the update information.

7. A network device comprising:

a processing component;

a first processor and a second processor;

wherein the processing component is operable to determine whether a multicast protocol-related packet is of a first type, and upon determining that the multicast-protocol related packet is of the first type, to send a copy of the multicast protocol-related packet to the first processor, and a copy of the multicast protocol-related packet to the second processor;

the first processor configurable to operate in an active mode, wherein the first processor is configurable to perform a set of multicast routing-related functions in the active mode; and

the second processor configurable to operate in a standby mode when the first processor is operating in the active mode, wherein the second processor is configurable to not perform the set of multicast routing-related functions in the standby mode;

wherein the first processor is further configurable to;

receive, from the processing component, a copy of the multicast protocol-related packet; and

update first multicast information maintained by the first processor based upon the copy of the multicast protocol-related packet received by the first processor, the first multicast information used by the first processor for performing the set of multicast routing-related functions;

wherein the second processor is further configurable to;

receive, from the processing component, a copy of the multicast protocol-related packet; and

update second multicast information maintained by the second processor based upon the copy of the multicast protocol-related packet received by the second processor.

8. The network device of claim 7 further comprising a linecard, wherein the linecard comprises the processing component.

9. The network device of claim 7 wherein the multicast protocol-related packet is a Protocol Independent Multicast (PIM) packet.

10. The network device of claim 9 wherein the first multicast information updated by the first processor comprises information related to neighbors of the network device that support PIM protocol.

11. The network device of claim 7 wherein the multicast protocol-related packet is an Internet Group Membership Protocol (IGMP) packet.

12. The network device of claim 11 wherein the first multicast information updated by the first processor comprises information related to the IGMP.

13. The network device of claim 7 wherein:

the first processor is configurable to communicate update information to the second processor, the update information comprising information indicative of a change made to the first multicast information; and

the second processor is configurable to update the second multicast information based upon the update information.