Overlay-Based Packet Steering

• US 20130163594A1
• Filed: 12/21/2011
• Published: 06/27/2013
• Est. Priority Date: 12/21/2011
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Sharma, Govind Prasad, Devireddy, Dileep K.
• Granted Patent: US 8,830,834 B2
• Time in Patent Office: Days
• US Class Current: 370/392
• CPC Class Codes: H04L 12/4633 Interconnection of networks using encapsulation techniques, e.g. tunneling
• CPC Class Codes: H04L 45/64 using an overlay routing layer
• CPC Class Codes: H04L 45/66 Layer 2 routing, e.g. in Ethernet based MAN's

Abstract

Network topology independent service deployment techniques, referred to as overlay-based packet steering techniques, are provided. In one example, a server destined packet is intercepted by an in-path network device enabled as a service classifier. The service classifier encapsulates the packet and inserts the packet into a service path to a service virtualization endpoint front ending one or more service nodes. In other words, the service virtualization endpoint receives the service-directed packet on an overlay-based service path. The service-directed packet includes a service header and a service overlay tunnel encapsulation. The service virtualization endpoint inspects the service header in the service-directed packet to identify a first service node to which the service-directed packet should be forwarded and, based on the inspection, forwards the service-directed packet, on the overlay-based service path, to the first service node.

Claims

1. A method comprising:

receiving, on an overlay-based service path, a service-directed packet at a first network device, wherein the service-directed packet comprises a service header and a service overlay tunnel encapsulation;

inspecting the service header in the service-directed packet to identify a first service node to which the service-directed packet should be forwarded;

based on the inspection, forwarding the service-directed packet to the first service node on the overlay-based service path; and

after the first service node applies a service on the service-directed packet, receiving, on the overlay-based service path, the service-directed packet back from the first service node.

2. The method of claim 1, wherein the service-directed packet was intercepted from a network flow intended for a destination device by a service classifier on a second network device and wherein the method further comprises:

after receiving the service-directed packet from the first service node, forwarding the service-directed packet to the destination device.

3. The method of claim 2, further comprising:

prior to forwarding the service-directed packet to the destination device, de-encapsulating the service-directed packet.

4. The method of claim 1, wherein the service-directed packet was intercepted by a service classifier on a second network device, and wherein the method further comprises:

after receiving the service-directed packet from the first service node, forwarding the service-directed packet back to the service classifier on the overlay-based service path.

5. The method of claim 1, further comprising:

after receiving the service-directed packet from the first service node, forwarding the service-directed packet to a second service node on the overlay-based service path.

6. The method of claim 1, wherein receiving a service-directed packet comprises:

receiving a service-directed packet having a layer 2 service overlay tunnel encapsulation.

7. The method of claim 6, wherein forwarding the service-directed packet to the first service node comprises:

forwarding the service-directed packet to the first service node with a layer 2 service overlay tunnel encapsulation.

8. The method of claim 6, further comprising:

encapsulating the service-directed packet with a layer 3 service overlay tunnel encapsulation; and

forwarding the service-directed packet having the layer 3 service overlay tunnel encapsulation to the first service node.

9. The method of claim 1, wherein receiving a service-directed packet comprises:

receiving a service-directed packet having a layer 3 service overlay tunnel encapsulation.

10. The method of claim 9, wherein forwarding the service-directed packet to the first service node comprises:

forwarding the service-directed packet to the first service node with a service overlay layer 3 tunnel encapsulation.

11. The method of claim 9, further comprising:

encapsulating the service-directed packet to include a layer 2 service overlay tunnel encapsulation; and

forwarding the service-directed packet having the layer 2 service overlay tunnel encapsulation to the first service node.

12. The method of claim 1, wherein inspecting the service header in the service-directed packet to identify a first service node to which the service-directed packet should be forwarded comprises:

performing a look-up in a path-forwarding table.

13. An apparatus comprising:

a plurality of network interfaces;

a processor coupled to the plurality of network interfaces and configured to;

receive, on an overlay-based service path, a service-directed packet at a first network device, wherein the service-directed packet comprises a service header and a service overlay tunnel encapsulation;

inspect the service header in the service-directed packet to identify a first service node to which the service-directed packet should be forwarded;

forward, based on the inspection, the service-directed packet to the first service node on the overlay-based service path; and

receive, on the overlay-based service path, the service-directed packet back from the first service node after the first service node applies a service on the service-directed packet.

14. The apparatus of claim 13, wherein the service-directed packet was intercepted from a network flow intended for a destination device by a service classifier on a second network device and wherein the processor is configured to forward the service-directed packet to the destination device after receiving the service-directed packet from the first service node.

15. The apparatus of claim 14, wherein the processor is configured to de-encapsulate the service-directed packet prior to forwarding the service-directed packet to the destination device.

16. The apparatus of claim 13, wherein the service-directed packet was intercepted by a service classifier on a second network device, and wherein the processor is configured to forward the service-directed packet back to the service classifier on the overlay-based service path after receiving the service-directed packet from the first service node.

17. The apparatus of claim 13, wherein the processor is configured to forward the service-directed packet to a second service node on the overlay-based service path after receiving the service-directed packet from the first service node.

18. The apparatus of claim 13, wherein the processor is configured to receive a service-directed packet having a layer 2 service overlay tunnel encapsulation.

19. The apparatus of claim 18, wherein the processor is configured to forward the service-directed packet to the first service node with a layer 2 service overlay tunnel encapsulation.

20. The apparatus of claim 18, wherein the processor is configured to encapsulate the service-directed packet with a layer 3 service overlay tunnel encapsulation, and forward the service-directed packet having the layer 3 service overlay tunnel encapsulation to the first service node.

21. The apparatus of claim 13, wherein the processor is configured to receive a service-directed packet having a layer 3 service overlay tunnel encapsulation.

22. The apparatus of claim 21, wherein the processor is configured to forward the service-directed packet to the first service node with a service overlay layer 3 tunnel encapsulation.

23. The apparatus of claim 21, wherein the processor is configured to encapsulate the service-directed packet to include a layer 2 service overlay tunnel encapsulation, and forward the service-directed packet having the layer 2 service overlay tunnel encapsulation to the first service node.

24. The apparatus of claim 13, wherein to inspect the service header in the service-directed packet, the processor is configured to perform a look-up in a path-forwarding table.

25. The apparatus of claim 13, wherein the processor comprises one or more application-specific integrated circuits.

26. The apparatus of claim 13, wherein the processor is configured to execute software in memory to performs its operations.

27. One or more computer readable storage media encoded with software comprising computer executable instructions and when the software is executed operable to:

receive, on an overlay-based service path, a service-directed packet at a first network device, wherein the service-directed packet includes a service header and a service overlay tunnel encapsulation;

inspect the service header in the service-directed packet to identify a first service node to which the service-directed packet should be forwarded;

based on the inspection, forward the service-directed packet to the first service node on the overlay-based service path; and

receive, on the overlay-based service path, the service-directed packet back from the first service node after the first service node applies a service on the service-directed packet.

28. The computer readable storage media of claim 27, wherein the service-directed packet was intercepted from a network flow intended for a destination device by a service classifier on a second network device and wherein the computer readable storage media further comprise instructions operable to:

forward the service-directed packet to the destination device after receiving the service-directed packet from the first service node.

29. The computer readable storage media of claim 27, wherein the service-directed packet was intercepted by a service classifier on a second network device, and wherein the computer readable storage media further comprise instructions operable to:

forward the service-directed packet back to the service classifier on the overlay-based service path after receiving the service-directed packet from the first service node.

30. The computer readable storage media of claim 27, further comprising instruction operable to forward the service-directed packet to a second service node on the overlay-based service path after receiving the service-directed packet from the first service node.