Dataplane-based seamless bidirectional forwarding detection monitoring for network entities

• US 10,447,571 B2
• Filed: 01/12/2018
• Issued: 10/15/2019
• Est. Priority Date: 01/12/2018
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Nainar, Nagendra Kumar, Pignataro, Carlos M.
• Primary Examiner(s): Sheikh, Ayaz R
• Assistant Examiner(s): Hampton, Tarell A
• Application Number:
  US15/869,322
• Publication Number:
  US 20190222500A1
• Time in Patent Office: 641 Days
• Field of Search: None
• CPC Class Codes: H04L 43/10 Active monitoring, e.g. heartbeat, ping or trace-route
• CPC Class Codes: H04L 45/34 Source routing
• CPC Class Codes: H04L 45/50 using label swapping, e.g. multi-protocol label switch [MPLS]
• CPC Class Codes: H04L 45/72 Routing based on the source address
• CPC Class Codes: H04L 45/745 Address table lookup; Address filtering

Abstract

Dataplane-based Seamless Bidirectional Forwarding Detection (S-BFD) monitoring for network entities is provided. In one embodiment, a method of S-BFD monitoring includes assigning, by a network element, a unique segment identifier (ID) to each entity of a plurality of entities that are monitored by the network element. The method includes receiving an S-BFD control packet at the network element, including a first segment ID associated with a particular entity. The method also includes performing a lookup operation for the first segment ID in stored data of the network element. Based on the lookup operation, when a first action is designated in the stored data for the first segment ID, the method includes returning the S-BFD control packet to its source, and, when a second action is designated in the stored data for the first segment ID, the method includes forwarding the S-BFD control packet to an S-BFD reflector session.

Claims

1. A computer-implemented method comprising:

assigning, by a network element, a unique segment identifier (ID) to each entity of a plurality of entities that are monitored by the network element;

receiving a seamless bidirectional forwarding detection (S-BFD) control packet at the network element, the S-BFD control packet including at least a first segment ID associated with a particular entity of the plurality of entities;

performing a lookup operation for the first segment ID in stored data of the network element; and

based on the lookup operation,

when a first action is designated in the stored data for the first segment ID, returning the S-BFD control packet to its source; and

when a second action is designated in the stored data for the first segment ID, forwarding the S-BFD control packet to an S-BFD reflector session.

2. The method of claim 1, wherein the S-BFD control packet further includes a first discriminator field associated with a first discriminator identifier (ID), a second discriminator field associated with a second discriminator identifier (ID), and a diagnostic field associated with a first diagnostic code.

3. The method of claim 2, wherein, when the first action is designated, the S-BFD control packet returned to its source includes the same first discriminator ID in the first discriminator field, the same second discriminator ID in the second discriminator field, and the same first diagnostic code in the diagnostic field as that of the S-BFD control packet received by the network element.

4. The method of claim 2, wherein, when the second action is designated, the method further comprising:

modifying the S-BFD control packet, by the S-BFD reflector session, to produce a modified S-BFD control packet by changing the first discriminator field to the second discriminator ID, change the second discriminator field to the first discriminator ID, and change the diagnostic field to a second diagnostic code.

5. The method of claim 4, further comprising transmitting the modified S-BFD control packet to the source of the received S-BFD control packet.

6. The method of claim 4, wherein the second diagnostic code indicates a failure of the particular entity associated with the first segment ID.

7. The method claim 1, further comprising:

receiving a plurality of S-BFD control packets at the network element, wherein each S-BFD control packet includes at least an indicated segment ID associated with a particular entity of the plurality of entities;

performing a lookup operation for each indicated segment ID in the stored data of the network element; and

based on the lookup operation,

when the first action is designated in the stored data for a particular indicated segment ID, returning that S-BFD control packet to its source; and

when the second action is designated in the stored data for a particular indicated segment ID, forwarding that S-BFD control packet to an S-BFD reflector session.

8. One or more non-transitory computer readable storage media encoded with instructions that, when executed by a processor of a network element, cause the processor to:

assign a unique segment identifier (ID) to each entity of a plurality of entities that are monitored by the network element;

receive a seamless bidirectional forwarding detection (S-BFD) control packet, the S-BFD control packet including at least a first segment ID associated with a particular entity of the plurality of entities;

perform a lookup operation for the first segment ID in stored data of the network element; and

based on the lookup operation,

when a first action is designated in the stored data for the first segment ID, return the S-BFD control packet to its source; and

when a second action is designated in the stored data for the first segment ID, forward the S-BFD control packet to an S-BFD reflector session.

9. The one or more non-transitory computer readable storage media of claim 8, wherein the S-BFD control packet further includes a first discriminator field associated with a first discriminator identifier (ID), a second discriminator field associated with a second discriminator identifier (ID), and a diagnostic field associated with a first diagnostic code.

10. The one or more non-transitory computer readable storage media of claim 9, wherein, when the first action is designated, cause the processor to:

return the S-BFD control packet to its source, wherein the returned S-BFD control packet includes the same first discriminator ID in the first discriminator field, the same second discriminator ID in the second discriminator field, and the same first diagnostic code in the diagnostic field as that of the received S-BFD control packet.

11. The one or more non-transitory computer readable storage media of claim 9, wherein, when the second action is designated, cause the processor to:

instantiate the S-BFD reflector session; and

modify the S-BFD control packet, by the S-BFD reflector session, to produce a modified S-BFD control packet by changing the first discriminator field to the second discriminator ID, change the second discriminator field to the first discriminator ID, and change the diagnostic field to a second diagnostic code.

12. The one or more non-transitory computer readable storage media of claim 11, further comprising instructions that cause the processor to transmit the modified S-BFD packet to the source of the received S-BFD control packet.

13. The one or more non-transitory computer readable storage media of claim 11, wherein the second diagnostic code indicates a failure of the particular entity associated with the first segment ID.

14. The one or more non-transitory computer readable storage media of claim 11, further comprising instructions that cause the processor to:

receive a plurality of S-BFD control packets, wherein each S-BFD control packet includes at least an indicated segment ID associated with a particular entity of the plurality of entities;

perform a lookup operation for each indicated segment ID in the stored data of the network element; and

based on the lookup operation,

when the first action is designated in the stored data for a particular indicated segment ID, return that S-BFD control packet to its source; and

when the second action is designated in the stored data for a particular indicated segment ID, forward that S-BFD control packet to an S-BFD reflector session.

15. An apparatus comprising:

a plurality of network ports configured to receive inbound packets and to send outbound packets, the plurality of network ports in communication with a plurality of entities that are monitored by the apparatus;

a memory;

a processor coupled to the memory and to the plurality of network ports, wherein the processor is configured to;

assign a unique segment identifier (ID) to each entity of the plurality of entities that are monitored by the apparatus;

receive a seamless bidirectional forwarding detection (S-BFD) control packet, the S-BFD control packet including at least a first segment ID associated with a particular entity of the plurality of entities;

perform a lookup operation for the first segment ID in stored data; and

based on the lookup operation,

when a first action is designated in the stored data for the first segment ID, return the S-BFD control packet to its source; and

when a second action is designated in the stored data for the first segment ID, forward the S-BFD control packet to an S-BFD reflector session.

16. The apparatus of claim 15, wherein the S-BFD control packet further includes a first discriminator field associated with a first discriminator identifier (ID), a second discriminator field associated with a second discriminator identifier (ID), and a diagnostic field associated with a first diagnostic code.

17. The apparatus of claim 16, wherein, when the first action is designated, the processor is configured to:

return the S-BFD control packet to its source, wherein the returned S-BFD control packet includes the same first discriminator ID in the first discriminator field, the same second discriminator ID in the second discriminator field, and the same first diagnostic code in the diagnostic field as that of the received S-BFD control packet.

18. The apparatus of claim 16, wherein, when the second action is designated, the processor is configured to:

instantiate the S-BFD reflector session; and

modify the S-BFD control packet, by the S-BFD reflector session, to produce a modified S-BFD control packet by changing the first discriminator field to the second discriminator ID, change the second discriminator field to the first discriminator ID, and change the diagnostic field to a second diagnostic code.

19. The apparatus of claim 18, wherein the second diagnostic code indicates a failure of the particular entity associated with the first segment ID.

20. The apparatus of claim 15, wherein the processor is further configured to:

receive a plurality of S-BFD control packets, wherein each S-BFD control packet includes at least an indicated segment ID associated with a particular entity of the plurality of entities;

perform a lookup operation for each indicated segment ID in the stored data; and

based on the lookup operation,

when the first action is designated in the stored data for a particular indicated segment ID, return that S-BFD control packet to its source; and

when the second action is designated in the stored data for a particular indicated segment ID, forward that S-BFD control packet to an S-BFD reflector.