Service Chain Header and Metadata Transport

• US 20160028640A1
• Filed: 07/22/2015
• Published: 01/28/2016
• Est. Priority Date: 07/22/2014
• Status: Active Grant

• Current Assignee: Huawei Cloud Computing Technologies Company Limited (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Zhang, Hong, Fourie, Louis
• Granted Patent: US 10,003,530 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 45/30 Routing of multiclass traffic
• CPC Class Codes: H04L 45/306 Route determination based on the nature of the carried application
• CPC Class Codes: H04L 67/288 Distributed intermediate devices, i.e. intermediate devices for interaction with other intermediate devices on the same level
• CPC Class Codes: H04L 67/561 Adding application-functional data or data for application control, e.g. adding metadata
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers

Abstract

Metadata may be embedded in a service chain header (SCH) appended to a packet that is forwarded over a service chain path. The metadata may include information that is used to process the packet at a downstream service function chain (SFC) entity on the service chain path. The metadata TLV field may identify a service action to be performed by a downstream SFC entity. For example, the metadata TLV field may instruct the downstream SFC entity to drop the packet, to redirect the packet (or a traffic flow associated with the packet), to mirror a traffic flow, to terminate a communication connection, to start or stop a packet accounting, and/or to apply a higher grade of service. In another embodiment, the metadata TLV field specifies an OAM service action list that identifies service actions that have been performed on the packet.

Claims

1. A method for service chain header processing in a communication network, the method comprising:

inserting, by an upstream service function chain (SFC) entity, a metadata Type-Length-Value (TLV) field into a service chain header (SCH) appended to a packet, wherein the SCH comprises a version field that indicates a version associated with the SCH, and wherein the metadata Type-Length-Value (TLV) field includes metadata information for processing the packet at a downstream SFC entity on a service chain path; and

forwarding the packet to the downstream SFC entity over the service chain path.

2. The method of claim 1, wherein the metadata TLV consists of a TLV class field, a type field immediately following the TLV class field, one or more reserved fields immediately following the type field, a length field immediately following the one or more reserved fields, and a metadata value field.

3. The method of claim 2, wherein the TLV class describes the scope of the Type field, the type field indicates a specific type of information carried in the metadata value field, and the length field indicates the length of the metadata value field.

4. The method of claim 1, wherein the metadata TLV field further includes a private (P) field that indicates whether an organizational unique identifier (OUI) field is present in the metadata TLV field.

5. The method of claim 4, wherein the P field indicates that the OUI field is present in the metadata TLV, the OUI field indicating a vendor specific identifier associated with vendor specific metadata information in the metadata TLV.

6. The method of claim 1, wherein the metadata information specifies an operation administration and management (OAM) operation that identifies a service action to be performed by the downstream SFC entity.

7. The method of claim 6, wherein the service action includes dropping a packet, redirecting a traffic flow, mirroring a traffic flow, terminating a communication connection, starting or stopping a packet accounting, applying a higher grade of service to the packet or a combination thereof.

8. The method of claim 6, wherein the metadata information specifies an OAM service action list that identifies service actions that have been performed on the packet.

9. The method of claim 1, wherein the metadata information specifies a target address that is used to carry an original destination internet protocol (IP) address of a terminating service function forwarder (SFF) over the service chain path.

10. The method of claim 1, wherein the upstream SFC entity is a classifier node, or an SFC Proxy server.

11. The method of claim 1, wherein the SCH further comprises a metadata length field indicating a length of the metadata TLV field.

12. An upstream service function chain (SFC) entity comprising:

a processor; and

a computer readable storage medium storing programming for execution by the processor, the programming including instructions to;

insert a metadata Type-Length-Value (TLV) field into a service chain header (SCH) appended to a packet, wherein the SCH comprises a version field that indicates a version associated with the SCH, and wherein the metadata Type-Length-Value (TLV) field includes metadata information for processing the packet at a downstream SFC entity on a service chain path; and

forward the packet to the downstream SFC entity over the service chain path.

13. A method for service chain header processing in a communication network, the method comprising:

receiving, by a downstream service function chain (SFC) entity, a packet over a service chain path, wherein the packet includes a service chain header (SCH) comprising a version field that indicates a version associated with the SCH and a metadata Type-Length-Value (TLV) field including metadata information; and

processing, by the downstream SFC, the packet in accordance with the metadata information included in the metadata TLV field embedded in the SCH.

14. The method of claim 13, wherein the metadata TLV consists of a TLV class field, a type field immediately following the TLV class field, one or more reserved fields immediately following the type field, a length field immediately following the one or more reserved fields, and a metadata value field.

15. The method of claim 14, wherein the TLV class describes the scope of the Type field, the type field indicates a specific type of information carried in the metadata value field, and the length field indicates the length of the metadata value field.

16. The method of claim 13 wherein the metadata TLV field further includes a private (P) field that indicates whether an organizational unique identifier (OUI) field is present in the metadata TLV field.

17. The method of claim 16, wherein the P field indicates the OUI field is present in the metadata TLV, the OUI field indicating that the metadata information in the metadata TLV is vender specific metadata.

18. The method of claim 13, wherein processing the packet in accordance with the metadata information specified by the metadata TLV field embedded in the SCH comprises performing, on the packet, a service action specified by operation administration and management (OAM) metadata embedded in the SCH.

19. The method of claim 18, wherein the service action includes dropping the packet, redirecting a traffic flow, mirroring a traffic flow, terminating a communication connection, starting or stopping a packet accounting, applying a higher grade of service to the packet, or a combination thereof.

20. The method of claim 13, wherein the metadata information specifies an OAM service action list that identifies service actions that have been performed on the packet.

21. The method of claim 13, wherein the metadata information specifies a target address that is used to carry an original destination internet protocol (IP) address of a terminating service function forwarder (SFF) over the service chain path.

22. The method of claim 21, wherein processing the packet in accordance with the metadata information specified by the metadata TLV embedded in the SCH comprises:

replacing, by the downstream SFC entity, a destination IP address of the packet with the target address specified by the metadata information when the downstream SFC entity is the last SFC entity on the service chain path.

23. The method of claim 13, wherein the upstream SFC entity is a classifier node or an SFC Proxy server.

24. The method of claim 13, wherein the SCH further comprises a metadata length field indicating a length of the metadata TLV field.

25. A downstream service function chain (SFC) entity comprising:

a processor; and

a computer readable storage medium storing programming for execution by the processor, the programming including instructions to;

receive a packet over a service chain path, wherein the packet includes a service chain header (SCH) comprising a version field that indicates a version associated with the SCH and a metadata Type-Length-Value (TLV) field including metadata information; and

process the packet in accordance with the metadata information included in the metadata TLV field embedded in the SCH.