Automation fallback to P2P LSPs for mLDP built multipoint-trees

• US 20070217428A1
• Filed: 03/16/2006
• Published: 09/20/2007
• Est. Priority Date: 03/16/2006
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Boers, Arjen, Wijnands, Ijsbrand, Meylor, John
• Granted Patent: US 8,107,473 B2
• Time in Patent Office: Days
• US Class Current: 370/395.500
• CPC Class Codes: H04L 12/18 for broadcast or conference , e.g. multicast
• CPC Class Codes: H04L 12/1845 broadcast or multicast in a specific location, e.g. geocast protocols for adapting network applications to user terminal location H04L67/52; services specially adapted for wireless communication networks making use of the location of users or terminals H04W4/02
• CPC Class Codes: H04L 2012/5641 Unicast/point-to-point
• CPC Class Codes: H04L 2012/5642 Multicast/broadcast/point-multipoint, e.g. VOD
• CPC Class Codes: H04L 2012/6416 Switch multicast
• 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 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/46 Cluster building
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]
• CPC Class Codes: H04L 45/502 Frame based

Abstract

A method of using a point-to-point (P2P) label switched path (LSP) to transmit multicast data packets partially through a multiprotocol label switched (MPLS) network when one or more label switched routers (LSRs) of the MPLS are not multicast label distribution protocol (mLDP) enabled. The P2P LSP can be used to transmit multicast data packets to the head end of a point-to-multipoint (P2MP) LSP created with mLDP enabled LSRs. The P2MP LSP can be used to transmit the multicast data packets through the MPLS network to intended receivers that are external to the MPLS network. When configuring the P2MP LSP, an mLDP enabled LSR receives a first message from a non-mLDP enabled MPLS core router in response to sending a label mapping message to the non-mLDP enabled MPLS core router. In response, a directed LDP session is created between the mLDP enabled LSR and an edge LSR in one embodiment in response to receiving the first message from an MPLS enabled core router. The directed LDP session can be used to transmit a label mapping message to an ingress LSR.

Claims

1. A method comprising:

a multiprotocol label switched (MPLS) enabled router receiving a packet from a first MPLS enabled edge router via a first label switched path (LSP);

the MPLS enabled router transmitting the packet to a second MPLS enabled edge router via a second LSP.

2. The method of claim 1 wherein the first LSP is a point-to-point (P2P) LSP and the second LSP is a point-to-multipoint (P2MP) LSP or branch thereof.

3. The method of claim 1 further wherein the MPLS enabled router is the tail end MPLS enabled router of the first LSP and the head end MPLS enabled router of the second LSP.

4. The method of claim 1 further comprising;

the MPLS enabled router replicating the data packet to produce a replicated data packet;

the MPLS enabled router transmitting the replicated data packet to a third MPLS enabled edge router via the second LSP.

23. The apparatus of claim 1 further comprising;

a fifth circuit configured to receive a data packet via a P2P LSP;

a sixth circuit configured to replicate the data packet to produce a replicated data packet;

a sixth circuit configured to send the replicated data packet to an MPLS enabled edge router via a P2MP LSP.

5. A method comprising:

an MPLS enabled router receiving a first message from an MPLS enabled core router in response to sending a label mapping message to the MPLS enabled core router;

creating a directed label distribution protocol (LDP) session with an MPLS enabled edge router in response to receiving the first message from an MPLS enabled core router.

6. The method of claim 5 wherein the label mapping message comprises a first value, wherein the first value was generated by a second MPLS enabled edge router as a function of a multicast group IP address.

7. The method of claim 6 wherein the first value was generated as a function of a multicast data packet source IP address.

8. The method of claim 7 wherein the label mapping message comprises an identity of the MPLS enabled edge router.

9. The method of claim 8 wherein the label mapping message comprises a label generated by the MPLS enabled router.

10. The method of claim 5 wherein the label mapping message is transmitted to the MPLS enabled edge router via the directed LDP session.

19. The system of claim 8 wherein the label mapping message comprises a label generated by the first MPLS enabled core router.

21. The method of claim 5 wherein the first message comprises an unknown forwarding equivalency class message.

11. An apparatus comprising:

a first circuit configured to create a label mapping message;

a second circuit configured to send the label mapping message to an MPLS enabled core router;

a third circuit configured to receive a first message from the MPLS enabled core router in response to the second circuit sending the label mapping message to the MPLS enabled core router;

a fourth circuit configured to send the label mapping message to a first MPLS enabled edge router via a directed LDP session in response to the third circuit receiving the first message.

12. The apparatus of claim 11 wherein the label mapping message comprises a first value, wherein the first value is generated by a second MPLS enabled edge router as a function of a multicast group IP address.

13. The apparatus of claim 12 wherein the first value is generated as a function of a multicast data packet source IP address.

14. The apparatus of claim 13 wherein the label mapping message comprises an identity of the MPLS enabled edge router.

22. The apparatus of claim 12 wherein the first value is generated as a function of a multicast data packet source IP address.

15. A system comprising:

first and second MPLS enabled edge routers coupled to each other via first and second MPLS enabled core routers;

wherein the first MPLS enabled edge router is configured to receive a protocol independent multicast (PIM) Join message and configured to generate a first value as a function of a multicast group IP address contained in the PIM Join message;

wherein first MPLS enabled core router is configured receive a first message from the second MPLS enabled core router in response to the first MPLS enabled core router sending a label mapping message to the second MPLS enabled core router;

wherein the first MPLS enabled core router is configured to create a directed LDP session with the second MPLS enabled edge router in response to receiving the first message from the second MPLS enabled core router.

16. The system of claim 15 wherein the label mapping message comprises the first value generated by the MPLS enabled edge router.

17. The system of claim 16 wherein the first value is generated as a function of a multicast data packet source IP address contained in the PIM Join message.

18. The system of claim 17 wherein the label mapping message comprises an identity of the second MPLS enabled edge router.

20. The apparatus of claim 15 wherein the label mapping message is sent to the second MPLS enabled edge router via the directed LDP session.