Granted Patent B2

US 9,369,379 · App. 14/502,628 · Granted Jun 14, 2016

Abstract

Claims (46)

1. A method for enabling validation of packets received from a label switched router (LSR) via a label switched path (LSP), the method comprising:

by an assigning LSR, associating each of at least one LSP label to forwarding equivalency class (FEC) bindings with a respective Epoch Label;

by the assigning LSR, storing each label/FEC binding and respective Epoch Label in a Label Forwarding Information Base (LFIB); and

by the assigning LSR, including, within each Label Mapping Message (LMM) advertising a label/FEC binding via a label distribution protocol (LDP), the respective Epoch Label;

wherein an LSP labeled packet including an Epoch Label not associated with the LSP label is deemed invalid.

2. The method of claim 1 , further comprising:

determining, using the LSP label of a received packet, an expected Epoch Label associated with the received packet; and

identifying a received packet as invalid if the Epoch Label of the received packet is not the expected Epoch Label.

3. The method of claim 1 , wherein said label/FEC bindings and Epoch Labels are advertised via the LDP.

4. The method of claim 3 , wherein said LDP substantially conforms to one or more of IETF RFC 5036, RSVP-TE and border gateway protocol (BGP).

5. The method of claim 1 , wherein said label/FEC bindings and epoch labels are stored in a label forwarding information base.

6. The method of claim 1 , wherein each Epoch Label associated with a label/FEC binding comprises a random number or one of a sequence of numbers.

7. The method of claim 1 , further comprising indicating Epoch Label Capability (ELC) with at least one adjacent LSR.

8. The method of claim 7 , wherein ECL of an LSR is indicated via an LDP ELC type-length-value (TLV).

9. The method of claim 7 , wherein said LDP ELC TLV is carried within an Optional Parameter portion of a Hello Message.

10. The method of claim 1 , wherein said Epoch Label is stored in an incoming Label Map (ILM) portion of said LFIB, and determining whether said received packet associated with an expected Epoch Label comprises comparing an Epoch Label within the received packet to an Epoch Label stored in the ILM and associated with the received packet LSP label.

11. An apparatus for enabling validation of packets received from a label switched router (LSR) via a label switched path (LSP), the apparatus comprising:

a processor and a memory communicatively connected to the processor, the processor configured to:

associate each of at least one LSP label to forwarding equivalency class (FEC) bindings with a respective Epoch Label;

store each label/FEC binding and respective Epoch Label in a Label Forwarding Information Base (LFIB); and

include, within each Label Mapping Message (LMM) advertising a label/FEC binding via a label distribution protocol (LDP), the respective Epoch Label;

wherein an LSP labeled packet including an Epoch Label not associated with the LSP label is deemed invalid.

12. The apparatus of claim 11 , wherein the processor is configured to:

determine, using the LSP label of a received packet, an expected Epoch Label associated with the received packet; and

identify a received packet as invalid if the Epoch Label of the received packet is not the expected Epoch Label.

13. The apparatus of claim 11 , wherein the processor is configured to:

in response to a determination that a label/FEC binding should be terminated, transmit a Label Withdraw Message (LWM) including a label/FEC binding and associated Epoch Label to at least one LSP.

14. The apparatus of claim 11 , wherein said apparatus comprises a label/FEC binding assigning LSR adjacent to at least one other LSR along an LSP.

15. An apparatus for processing packets prior to transmission toward a next label switched router (LSR) via a label switched path (LSP), the apparatus comprising:

a processor and a memory communicatively connected to the processor, the processor configured to:

configure a transmission packet to include an LSP label bound to the forward equivalency class (FEC) including the transmission packet; and

configure the transmission packet to include an Epoch Label associated with the LSP label.

16. The apparatus of claim 15 , wherein said packet is configured using information stored in a Next Hop Label Forwarding Entry (NHLFE) within a Forwarding Information Base (LFIB) associated with the apparatus.

17. The apparatus of claim 16 , wherein the processor is configured to:

receive a Label Mapping Message (LMM) including a label/FEC binding and an associated Epoch Label; and

store said label/FEC binding and associated Epoch Label within said NHLFE.

18. The apparatus of claim 17 , wherein the processor is configured to:

receive a Label Withdraw Message (LWM) including at least a label/FEC binding;

delete said label/FEC binding and any associated Epoch Label from said NHLFE; and

transmit a Label Release Message (LRM).

19. The apparatus of claim 15 , wherein said apparatus comprises an LSR adjacent to a label/FEC binding assigning LSR along an LSP.

20. A tangible and non-transient computer readable storage medium storing instructions which, when executed by a computer, adapt the operation of the computer to provide a method for enabling validation of packets received from a label switched router (LSR) via a label switched path (LSP), the method comprising:

associating each of at least one LSP label to forwarding equivalency class (FEC) bindings with a respective Epoch Label;

storing each label/FEC binding and respective Epoch Label in a Label Forwarding Information Base (LFIB); and

including, within each Label Mapping Message (LMM) advertising a label/FEC binding via a label distribution protocol (LDP), the respective Epoch Label;

wherein an LSP labeled packet including an Epoch Label not associated with the LSP label is deemed invalid.

Assignments (12)