Validation of Chained Network Services

• US 20150092564A1
• Filed: 09/26/2014
• Published: 04/02/2015
• Est. Priority Date: 09/27/2013
• Status: Active Grant

• Current Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Aldrin, Sam K.
• Granted Patent: US 9,917,745 B2
• Time in Patent Office: Days
• US Class Current: 370/241.1
• CPC Class Codes: H04L 43/55 Testing of service level quality, e.g. simulating service usage

Abstract

A method implemented in a network element, the method comprising identifying a first service function (SF) for validation, the first SF being associated with a service function chain (SFC), being applied to a data flow, and operating on a first network node, encoding one or more tests associated with the first SF in an operations, administration, and management (OAM) packet, and transmitting a validation request comprising the OAM packet towards the first SF to request validation of the first SF by execution of the tests.

Claims

1. A method implemented in a network element, the method comprising:

identifying a first service function (SF) for validation, the first SF being associated with a service function chain (SFC), being applied to a data flow, and operating on a first network node;

encoding one or more tests associated with the first SF in an operations, administration, and management (OAM) packet; and

transmitting a validation request comprising the OAM packet towards the first SF to request validation of the first SF by execution of the tests.

2. The method of claim 1, further comprising determining to validate the entire SFC, wherein the SFC comprises a plurality of SFs, including the first SF, each of the plurality of SFs being applied to the data flow, and wherein the tests encoded in the OAM packet further comprise tests for each of the SFC SFs.

3. The method of claim 2, wherein at least two of the plurality of SFs operate on different layers of the Open Systems Interconnect (OSI) model.

4. The method of claim 1, further comprising:

setting an overlay header time to live (TTL) field in the OAM packet to a number of network hops to an ingress SF of the SFC; and

setting a network service header TTL to a number of SF hops to the first SF to allow the SFC to forward the tests to the first SF.

5. The method of claim 1, wherein the determination to validate the first SF is made in response to a request from a network management system, a path head end node, a source associated with the data flow in another network domain, or combinations thereof.

6. The method of claim 1, wherein the validation request is transmitted toward the first SF via a proxy and an ingress SF of the SFC.

7. The method of claim 1, further comprising encoding SF identifiers (IDs) or SF metadata in the OAM packet to identify associations between the SFs the tests.

8. The method of claim 1, further comprising receiving a validation response from a headend network element associated with the first SF, wherein the validation response indicates results of the tests.

9. The method of claim 8, wherein the tests are associated with a plurality of SFs in the SFC, including the first SF, wherein the validation response is received via a validation results aggregator, and wherein the validation response results of the tests include results from each of the SFs.

10. The method of claim 1, wherein each of the tests are encoded in a test request encoding comprising a test type field indicating the associated test, a trigger type field indicating a trigger for the associated test, a timeout for the associated test, and test data for the associated test.

11. A network node comprising:

a transmitter;

a receiver; and

a processor coupled to the transmitter and the receiver and configured to cause the network node to;

execute a local service function associated with a service function chain, wherein executing the local service function comprises performing an operation on all messages associated with a data flow;

receive, via the receiver, a validation request comprising an operations, administration, and management (OAM) packet requesting validation of a plurality of service functions associated with the service function chain, wherein the OAM packet comprises a plurality of tests;

execute the local service function on each valid test directed to the local service function; and

populate a validation response with results associated each test directed to the local service function.

12. The network node of claim 11, wherein the transmitter is configured to forward the validation request to a second network node operating a remote service function associated with the service function chain for validation of the remote service function.

13. The network node of claim 11, wherein the processor is further configured to cause the network node to include the validation response in the validation request.

14. The network node of claim 11, wherein the processor is further configured to determine at least one of the tests is directed to the local service function when a service header time to live (TTL) field of the validation request is set to zero.

15. The network node of claim 14, wherein the processor is further configured to:

determine the validation request comprises unexecuted tests directed to a remote service function;

obtain a number of service hops to the remote service function;

update the service header TTL field of the validation request to indicate the number of service hops to the remote service function; and

forward the validation request toward the remote service function via the transmitter.

16. The network node of claim 11, wherein the validation request comprises an OAM payload field, and wherein the OAM payload field comprises an indication of each service function to be validated and an overall response field indicating overall results of tests associated with each service function.

17. The network node of claim 16, wherein the validation request further comprises a service time to live (TTL) hops field for each service function to be validated to support updating a service header of the OAM packet prior to forwarding the OAM packet.

18. A method comprising:

encapsulating an operations, administration, and management (OAM) message with a service function chain (SFC) header for testing a SFC component, wherein the SFC component comprises an ordered set of service functions (SFs) forming an SFC; and

transmitting the OAM message toward a network element implementing at least a portion of the SFC component to validate a policy of the SFC component.

19. The method of claim 18, wherein the OAM message is transmitted periodically to validate reachability of a service function (SF) in the SFC component to provision a continuity check of the SF or SFC and notify of failure upon failure detection.

20. The method of claim 18, wherein the OAM message is transmitted as part of a tracing function triggering an action from every transit device associated with the SFC using a time to live (TTL) function.