Protocol Independent Multicast Last Hop Router Discovery

• US 20120327764A1
• Filed: 06/22/2012
• Published: 12/27/2012
• Est. Priority Date: 06/22/2011
• Status: Active Grant

• Current Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Han, Lin, Li, Renwei
• Granted Patent: US 9,030,926 B2
• Time in Patent Office: Days
• US Class Current: 370/219
• CPC Class Codes: H04L 12/185 with management of multicast group membership
• CPC Class Codes: H04L 12/1877 Measures taken prior to transmission
• CPC Class Codes: H04L 12/1881 with schedule organisation, e.g. priority, sequence management

Abstract

Disclosed is an apparatus comprising a first network node configured to transmit a first message to a second network node, wherein the first message comprises data designating the first network node as a member of a first multicast channel, and wherein the first message comprises data indicating a network address a third network node that is designated as a last hop router (LHR) of the first multicast channel. Also disclosed is a method comprising sending, by a first network node, a protocol independent multicast (PIM) join message, wherein the PIM join message comprises the network address of a PIM channel last hop router (LHR).

Claims

1. An apparatus comprising:

a first network node configured to transmit a first message to a second network node,

wherein the first message comprises data designating the first network node as a member of a first multicast channel, and

wherein the first message comprises data indicating a network address of a third network node that is designated as a last hop router (LHR) of the first multicast channel.

2. The apparatus of claim 1, wherein the first network node is not the third network node.

3. The apparatus of claim 1, wherein the first multicast channel is a Protocol Independent Multicast (PIM) channel.

4. The apparatus of claim 1, wherein the first network node receives a second message from a downstream member of the first multicast channel prior to transmitting the first message, and wherein the second message comprises data indicating the network address of the third network node.

5. The apparatus of claim 4, wherein the first network node comprises a table, and wherein the first network node is further configured to store the network address of the third network node and information indicating that the third network node is an LHR of the first multicast channel in the table.

6. The apparatus of claim 5, wherein the first network node is further figured to delete from the table information related to the third network node if the third network node ceases to be a downstream node or ceases to be a member of the first multicast channel.

7. The apparatus of claim 6, wherein the first network node determines that the third network node has ceased to be a downstream node by sensing a downstream link failure.

8. The apparatus of claim 6, wherein the first network node determines that the third network has ceased to be a member of the first multicast channel based on information received in a join message or a prune message.

9. The apparatus of claim 1, wherein the first message further comprises data indicating the network addresses of a fourth network node, and wherein the fourth network node is designated as an LHR of a second multicast channel.

10. The apparatus of claim 9, wherein the first multicast channel and the second multicast channel are the same channel.

11. An apparatus comprising:

a first network node configured to receive a message from a second network node,

wherein the message comprises data designating the second network node as a member of a multicast channel, and

wherein the message comprises data indicating a network address of a third network node that is designated as a last hop router (LHR) of the multicast channel.

12. The apparatus of claim 11, wherein the first network node is designated as a first hop router (FHR) of the multicast channel, and wherein the multicast channel is implemented using protocol independent multicast (PIM) source specific mode (SSM), PIM sparse mode (SM), PIM dense mode (DM), or PIM bidirectional mode (BIDIR).

13. The apparatus of claim 11, wherein the message further comprises a quality of service (QoS) request, and wherein the first network node is configured to transmit a QoS fail message to the third network node if QoS provisioning associated with the QoS request could not be satisfied.

14. The apparatus of claim 11, wherein the first network node is further configured to send the network address of the third network node to a source of the multicast channel for use in multicast accounting.

15. The apparatus of claim 11, wherein the first network node is further configured to send the network address of the third network node to a source of the multicast channel for use in multicast failure testing.

16. A method comprising:

sending, by a first network node, a protocol independent multicast (PIM) join message,

wherein the PIM join message comprises the network address of a PIM channel last hop router (LHR).

17. The method of claim 16, wherein the PIM join message is encoded in a type length value (TLV), and wherein the TLV comprises:

an Attribute Type field comprising data indicating that the TLV is a LHR discovery TLV,

at least one Unicast Destination Address field comprising a network address of a network node designated as a LHR for a multicast channel, and

a Number of Destinations field comprising data indicating the number of Unicast Destination Address fields encoded in the TLV.

18. The method of claim 16 further comprising receiving a PIM prune message associated with second LHR, wherein the prune message indicates that a client device attached to a second LHR has left the PIM channel, and wherein the join message is sent in response to the prune message.

19. The method of claim 16, wherein the PIM join message is sent in response to a network link failure, and wherein the link failure occurs in a downstream link connected to the first network node.

20. The method of claim 16, wherein the PIM join message comprises the network address of the LHR if the LHR is designated as an important LHR by a user.