Service-specific forwarding in an LDP-RSVP hybrid network

• US 7,826,482 B1
• Filed: 12/20/2006
• Issued: 11/02/2010
• Est. Priority Date: 11/17/2006
• Status: Active Grant

• Current Assignee: Juniper Networks Incorporated
• Original Assignee: Juniper Networks Incorporated
• Inventors: Sheth, Nischal, Minei, Ina, Ayyangar, Arthi R., Kodeboyina, Chaitanya
• Primary Examiner(s): Sheikh; Ayaz R
• Assistant Examiner(s): Aga; Sori A
• Application Number:
  US11/642,162
• Time in Patent Office: 1,413 Days
• Field of Search: None
• US Class Current: 370/467
• CPC Class Codes: H04L 45/24 Multipath
• CPC Class Codes: H04L 45/306 Route determination based on the nature of the carried application
• CPC Class Codes: H04L 45/3065 for real time traffic
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]

Abstract

A router receives a control plane message for constructing a first LSP to a destination within a network that conforms to a first type of LSP. The control plane message includes a label for the first LSP and an identifier that identifies a first type of data traffic. The router receives a second control plane message for constructing a second LSP that conforms to the first type of LSP. The second control plane message includes a label for the second LSP and an identifier that identifies a second type of data traffic. The router installs forwarding state in accordance with policies that associate the first and second types of data traffic with different LSPs of a second type that each traverse different paths through the network, and forwards packets via the interface in accordance with the installed forwarding state.

Claims

1. A method for forwarding network traffic in a network, comprising:

receiving, at a router, a control plane message for constructing a first label switched path (LSP) to a destination within a network, wherein the first LSP conforms to a first type of LSP, and wherein the control plane message includes a label (L1) for the first LSP and an identifier (I1) that identifies a first type of data traffic;

receiving, at the router, a second control plane message for constructing a second LSP within the network to the destination, wherein the second LSP conforms to the first type of LSP, and wherein the second control plane message includes a label (L2) for the second LSP and an identifier (I2) that identifies a second type of data traffic;

installing forwarding state in accordance with policies that associate the first type of data traffic and the second type of data traffic with different LSPs of a second type that each traverse different paths through the network to associate the labels for the LSPs of the first type with respective LSPs of the second type such that, in accordance with the policies, each of the LSPs of the first type is tunneled over the respective LSPs of the second type so that the first type of data traffic and the second type of data traffic will travel over the respective LSPs of the second type; and

forwarding packets in accordance with the installed forwarding state.

2. The method of claim 1, wherein the policies control the installation of forwarding state with respect to the association of the labels for the LSPs of the first type with labels for the LSPs of the second type.

3. The method of claim 1, wherein the method for forwarding network traffic in a network comprises a method for forwarding traffic from the router to a downstream router, and wherein receiving the first and second control plane messages comprise receiving the first and second control plane messages from the downstream router.

4. The method of claim 1, further comprising:

receiving, with the router, packets that include a label identifying an LSP of the first type, wherein the packets do not include an identifier identifying the type of data traffic associated with the packets; and

wherein forwarding the packets in accordance with the installed forwarding state comprises forwarding the packets such that packets associated with the first type of data traffic are forwarded along a first LSP of the second type toward the destination that provides the first type of treatment, and packets associated with the second type of data traffic are forwarded along a second LSP of the second type toward the destination that provides the second type of treatment, wherein the first and second LSPs of the second type traverse different paths through the network.

5. The method of claim 1, wherein the first control plane message and the second control plane message conform to a label distribution protocol.

6. The method of claim 1, further comprising:

receiving packets associated with the first type of data traffic;

forwarding the packets associated with the first type of data traffic along a first LSP of the second type;

receiving packets associated with the second type of data traffic; and

forwarding the packets associated with the second type of data traffic along a second LSP of the second type that traverses a path through the network different than that of the first LSP of the second type,

wherein the packets associated with the first type of data traffic and the packets associated with the second type of data traffic belong to the same Quality of Service (QoS) class.

7. The method of claim 1, wherein the LSPs of the first type comprise Label Distribution Protocol (LDP) LSPs, and wherein the LSPs of the second type comprise Resource Reservation Protocol (RSVP) LSPs.

8. The method of claim 7, wherein the policies:

associate voice data traffic with low latency RSVP LSPs,

associate geographically constrained data traffic with RSVP LSPs that conform to the geographic constraint, and

associate general purpose data traffic with general purpose RSVP LSPs.

9. The method of claim 1, wherein the first type of data traffic is voice data traffic, and wherein the second type of data traffic is general purpose data traffic.

10. The method of claim 1, wherein the first type of data traffic is geographically constrained data traffic, and wherein the second type of data traffic is general purpose data traffic.

11. The method of claim 1, wherein the identifiers are specified within a forwarding equivalence class (FEC) of the respective control plane message.

12. The method of claim 1, wherein the identifier for the type of data traffic is a loopback address of an egress router of the second type of LSP.

13. The method of claim 1, wherein the identifier is a tag associated with a forwarding equivalence class (FEC).

14. The method of claim 1, wherein the identifier is a community identifier.

15. The method of claim 14, wherein the first and second LSPs are established using the Border Gateway Protocol (BGP), and wherein the community identifier is a BGP community identifier.

27. The method of claim 1, wherein the policies associate the first type of data traffic with a first LSP of the second type that provides the first type of treatment, and associate the second type of data traffic with a second LSP of the second type that provides the second type of treatment.

28. The method of claim 1,

wherein for the first type of data traffic received on the first LSP, the installed forwarding state specifies to swap the label L1 and push a label associated with a first LSP of the second type, and

wherein for the second type of data traffic received on the second LSP, the installed forwarding state specifies to swap the label L2 and push a label associated with a second LSP of the second type.

16. A router comprising:

an interface for receiving;

a control plane message for constructing a first label switched path (LSP) to a destination within a network, wherein the first LSP conforms to a first type of LSP, and wherein the control plane message includes a label (L1) for the first LSP and an identifier (11) that identifies a first type of data traffic, and

a second control plane message for constructing a second LSP within the network to the destination, wherein the second LSP conforms to the first type of LSP, and wherein the second control plane message includes a label (L2) for the second LSP and an identifier (I2) that identifies a second type of data traffic; and

a control unit that;

installs forwarding state in accordance with policies that associate the first type of data traffic and the second type of data traffic with different LSPs of a second type that each traverse different paths through the network to associate the labels for the LSPs of the first type with respective LSPs of the second type such that, in accordance with the policies, each of the LSPs of the first type is tunneled over the respective LSPs of the second type so that the first type of data traffic and the second type of data traffic will travel over the respective LSPs of the second type, and

forwards packets via the interface in accordance with the installed forwarding state.

17. The router of claim 16, wherein the policies control installation by the control unit of the forwarding state with respect to the association of the labels for the LSPs of the first type with labels for the LSPs of the second type.

18. The router of claim 16,

wherein the interface receives packets that include a label identifying an LSP of the first type, wherein the packets do not include an identifier identifying the type of data traffic associated with the packets;

and

wherein the control unit forwards the packets in accordance with the installed forwarding state such that packets associated with the first type of data traffic are forwarded along a first LSP of the second type toward the destination, and packets associated with the second type of data traffic are forwarded along a second LSP of the second type toward the destination, wherein the first and second LSPs of the second type traverse different paths through the network.

19. The router of claim 16, wherein the first control plane message and the second control plane message conform to a label distribution protocol.

20. The router of claim 16, wherein the identifiers are specified within one of a forwarding equivalence class (FEC) of the respective control plane message, a tag associated with a FEC, and a community identifier.

21. The router of claim 16, wherein the LSPs conforming to the first type of LSP are Label Distribution Protocol (LDP) LSPs, wherein the LSPs of the second type is are Resource Reservation Protocol (RSVP) LSPs.

22. A system comprising:

a first router; and

a second router coupled to the first router by a plurality of Resource Reservation Protocol (RSVP) label switched paths (LSPs), wherein the RSVP LSPs traverse different paths between the first router and the second router within a network,

wherein the first router dynamically installs forwarding state in response to a plurality of control plane messages received from the second router,

wherein each of the control plane messages includes a different Label Distribution Protocol (LDP) label identifying a different LDP LSP and a different identifier identifying a type of traffic,

wherein the first router installs the forwarding state by applying policies that associate different types of data traffic with different RSVP LSPs from among the plurality of RSVP LSPs to associate each of the LDP labels with a respective RSVP label identifying an RSVP LSP such that, in accordance with the policies, each of the LDP LSPs is tunneled over the respective RSVP LSP so that traffic of different types will travel over the respective RSVP LSPs, and

wherein the first router receives traffic of different types along the LDP LSP and forwards the traffic of different types along the different paths of the RSVP LSPs to the second router.

23. The system of claim 22, wherein the first router:

receives packets associated with the first type of data traffic and forwards the packets associated with the first type of data traffic along a first RSVP LSP to the second router, and receives packets associated with the second type of data traffic and forwards the packets associated with the second type of data traffic along a second RSVP LSP to the second router that traverses a path through the network different than that of the first RSVP LSP,

wherein the packets associated with the first type of data traffic and the packets associated with the second type of data traffic belong to the same Quality of Service (QoS) class.

24. The system of claim 22, wherein the identifier is one of an identifier specified within a forwarding equivalence class (FEC) of the label map message, a tag associated with a FEC, and a community identifier.

25. The system of claim 22, further comprising a provider edge router within the network, wherein the provider edge router sends to the second router control plane messages having different identifiers for each type of data traffic requiring a different type of path through the network.

26. A non-transitory computer-readable medium comprising instructions for causing a programmable processor to forward network traffic in a network, the instructions causing the programmable processor to:

receive, at a router, a control plane message for constructing a first label switched path (LSP) to a destination within a network, wherein the first LSP conforms to a first type of LSP, and wherein the control plane message includes a label (L1) for the first LSP and an identifier (11) that identifies a first type of data traffic that requires a first type of treatment;

receive, at the router, a second control plane message for constructing a second LSP within the network to the destination, wherein the second LSP conforms to the first type of LSP, and wherein the second control plane message includes a label (L2) for the second LSP and an identifier (I2) that identifies a second type of data traffic that requires a second type of treatment;

install forwarding state in accordance with policies that associate the first type of data traffic and the second type of data traffic with different LSPs of a second type that each traverse different paths through the network to associate the labels for the LSPs of the first type with respective LSPs of the second type; and

forward packets in accordance with the installed forwarding state.