Load Balancing Method, Device and System for Service Function Chain

• US 20180054389A1
• Filed: 09/23/2015
• Published: 02/22/2018
• Est. Priority Date: 03/20/2015
• Status: Active Grant

• Current Assignee: ZTE Corporation
• Original Assignee: ZTE Corporation
• Inventors: AO, Ting
• Granted Patent: US 10,447,600 B2
• Time in Patent Office: Days
• CPC Class Codes: H04L 45/24 Multipath
• CPC Class Codes: H04L 45/38 Flow based routing
• CPC Class Codes: H04L 45/64 using an overlay routing layer
• CPC Class Codes: H04L 47/125 by balancing the load, e.g. traffic engineering
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers

Abstract

Provided are a method for load balancing of a Service Function Chain (SFC), a Service Function forwarder (SFF), a classification device, a controller and an SFC system. The method includes: an SFF receives a packet, herein an SFC header of the packet carries a Service Function Chain Flow Identifier (SFCFID); and the SFF forwards the packet in a load balancing path according to the SFCFID carried in the SFC header of the packet.

Claims

1. A method for load balancing of a Service Function Chain, SFC, comprising:

receiving, by a Service Function Forwarder, SFF, a packet, wherein an SFC header of the packet carries a Service Function Chain Flow Identifier, SFCFID; and

forwarding, by the SFF, the packet in a load balancing path according to the SFCFID carried in the SFC header of the packet.

2. The method according to claim 1, further comprising:

before the SFF forwards the packet in the load balancing path according to the SFCFID carried in the SFC header of the packet, reading, by the SFF, the SFCFID carried in the SFC header of the packet according to a load balancing identifier carried in the SFC header of the packet or a load balancing path to which a next hop of the SFF belongs.

3. The method according to claim 1, wherein

the forwarding, by the SFF, the packet in a load balancing path according to the SFCFID carried in the SFC header of the packet comprises:

when the SFF is connected to two or more SF entities,

after the SFF receives a packet sent by a classification device or an SFF connected to a last hop SF entity, selecting one of the two or more SF entities to forward the packet according to the SFCFID carried in the SFC header of the packet;

or,

when a next hop of the SFF comprises two or more SF entities, selecting, by the SFF, one of load balancing paths to forward the packet according to the SFCFID carried in the SFC header of the packet comprises;

after the SFF receives a packet sent by a connected SF entity, sending the packet to an SFF connected to one of the two or more SF entities according to the SFCFID carried in the SFC header of the packet.

4. The method according to claim 1, further comprising:

adding a new SF entity in an SFC path, wherein the new SF entity is used for bearing load balancing for an original SF entity;

sending, by a controller, an SF registration message to an SFF connected to the new SF entity; and

/or, when the SFF corresponding to the new SF entity is not on the SFC path, sending, by the controller, a forwarder registration message to an SFF connected to a last hop of the original SF entity.

5. The method according to claim 4, further comprising:

sending, by the controller, a load balancing path adding message to a classification device or a load balancer; and

encapsulating, by the classification device, an SFCFID in an SFC header of a packet according to the received load balancing path adding message;

or, encapsulating, by the load balancer, an SFCFID in an SFC header of a packet according to the received load balancing path adding message;

or, when needing to select a load balancing path for forwarding a packet, notifying, by the classification device, the controller of the packet, and receiving a corresponding SFCFID sent by the controller, and encapsulating the corresponding SFCFID in the SFC header of the packet.

6. The method according to claim 1, further comprising:

receiving, by the SFF, an SF registration message sent by a controller, and adding, according to the SF registration message, a corresponding new SF entity in a path indicated by a corresponding SFPID;

and/or,

receiving, by the SFF, a forwarder registration message sent by the controller.

7. The method according to claim 6, wherein the adding, according to the SF registration message, a corresponding new SF entity in a path indicated by a corresponding SFPID comprises:

reading, by the SFF, an SFPID in the SF registration message, and judging, according to the SFPID in the SF registration message, whether the SFF is on the path indicated by the SPFID;

when a judgment result is that the SFF is on the path indicated by the SPFID, adding, by the SFF, the new SF entity as an SF entity connected to the SFF; and

when a judgment result is that the SFF is not on the path indicated by the SPFID, adding, by the SFF, an SFC path where the new SF entity is located into a local forwarding table.

8. The method according to claim 6, wherein

the SF registration message comprises an SFPID and an identifier corresponding to the new SF entity.

9. The method according to claim 6, wherein

the forwarder registration message comprises an SFPID, an identifier of the new SF entity, and information for indicating a position of the new SF entity in an SFC.

10. The method according to claim 6, further comprising:

adding, by the SFF, the new SF entity as a next hop of the SFF according to the forwarder registration message.

11. The method according to claim 1, wherein

the forwarding, by the SFF, the packet in a load balancing path according to the SFCFID carried in the SFC header of the packet comprises:

when selecting a load balancing path, acquiring, by the SFF, a selection of a next hop by searching a load balancing path table or a specific algorithm according to the SFCFID carried in the SFC header of the packet;

and

the method further comprising;

when selecting the load balancing path, searching, by the SFF, the load balancing path table to determine whether the load balancing path table contains a load balancing path corresponding to the SFCFID, and if the load balancing path corresponding to the SFCFID is searched, forwarding the packet through the load balancing path;

if the load balancing path corresponding to the SFCFID is not searched, selecting a load balancing path to forward the packet by calculation, and recording a correspondence between the SFCFID and the load balancing path in the load balancing path table;

or,

when selecting the load balancing path, searching, by the SFF, the load balancing path table to determine whether the load balancing path table contains a load balancing path corresponding to the SFCFID, and if the load balancing path corresponding to the SFCFID is searched, forwarding the packet through the load balancing path;

if the load balancing path corresponding to the SFCFID is not searched, selecting a load balancing path to forward the packet by calculation, recording a correspondence between the SFCFID and the load balancing path in the load balancing path table, and recording the correspondence in a load balancing path table of a symmetric SFC path corresponding to the present SFC path.

13. The method according to claim 1, further comprising:

receiving, by the SFF, an SF deregistration message; and

after receiving the SF deregistration message sent by the controller, deleting, by the SFF, a corresponding load balancing path and entries in a corresponding load balancing path table.

14. The method according to claim 1, further comprising:

sending, by the controller, a load balancing path deleting message to a classification device or a load balancing controller; and

recycling, by the classification device or the load balancing controller, a corresponding SFCFID according to the received load balancing path deleting message.

27. A computer storage medium in which computer-executable instructions are stored, and the computer-executable instructions being used to execute the method according to claim 1.

12. (canceled)

15. A Service Function Forwarder, SFF, comprising:

a receiving unit, configured to receive a packet, wherein a Service Function Chain, SFC, header of the packet carries a Service Function Chain Flow Identifier, SFCFID; and

a forwarding unit, configured to forward the packet in a load balancing path according to the SFCFID carried in the SFC header of the packet.

16. The SFF according to claim 15, wherein

the receiving unit comprises a first receiving module, configured to receive a packet sent by a classification device or an SFF connected to a last hop SF entity;

and

the forwarding unit comprises a first forwarding module configured to, when the SFF is connected to two or more SF entities and after receiving the packet sent by the classification device or the SFF connected to the last hop SF entity, select one of the two or more SF entities to forward the packet according to the SFCFID carried in the SFC header of the packet;

or

the receiving unit further comprises a second receiving module, configured to receive a packet sent by a connected SF entity; and

the forwarding unit further comprises a second forwarding module configured to, when a next hop of the SFF comprises two or more SF entities, and after receiving the packet sent by the connected SF entity, send the packet to an SFF connected to one of the two or more SF entities according to the SFCFID carried in the SFC header of the packet;

or

the forwarding unit further comprising one or more of a first selection module, a second selection module and a third selection module, wherein

the first selection module is configured to, when selecting a load balancing path, acquire a selection of a next hop by searching a load balancing path table or a specific algorithm according to the SFCFID carried in the SFC header of the packet;

the second selection module is configured to, when selecting the load balancing path, search the load balancing path table to determine whether the load balancing path table contains a load balancing path corresponding to the SFCFID, and if the load balancing path corresponding to the SFCFID is searched, forward the packet through the load balancing path; and

if the load balancing path corresponding to the SFCFID is not searched, calculate a next hop in a load balancing path, and record a correspondence between the SFCFID and the load balancing path in the load balancing path table; and

the third selection module is configured to, when selecting the load balancing path, search the load balancing path table to determine whether the load balancing path table contains a load balancing path corresponding to the SFCFID, and if the load balancing path corresponding to the SFCFID is searched, forward the packet through the load balancing path; and

if the load balancing path corresponding to the SFCFID is not searched, calculate a next hop in a load balancing path, record a correspondence between the SFCFID and the load balancing path in the load balancing path table, and record the correspondence in a load balancing path table of a symmetric SFC path corresponding to the present SFC path.

18. The SFF according to claim 15, further comprising an update unit, and the update unit comprising:

a third receiving module, configured to receive an SF registration message, wherein the SF registration message comprises a Service Function Path Identifier, SFPID, and an identifier corresponding to a new SF entity;

a judgment module, configured to, after receiving the SF registration message, read the SFPID in the SF registration message, and judge, according to the SFPID in the SF registration message, whether the SFF is on a path indicated by the SFPID;

a first update module, configured to, when a judgment result is that the SFF is on the path indicated by the SPFID, enable the SFF to add the new SF entity as an SF entity connected to the SFF;

a second update module, configured to, when a judgment result is that the SFF is not on the path indicated by the SPFID, enable the SFF to add an SFC path where the new SF entity is located into a local forwarding table;

and/or, the update unit further comprising a fourth receiving module and a third update module, wherein

the fourth receiving module is configured to receive a forwarder registration message, wherein the forwarder registration message comprises an SFPID, an identifier of the new SF entity, and information for indicating a position of the new SF entity in an SFC; and

the third update module is configured to, after receiving the forwarder registration message sent by a controller, add the new SF entity as a next hop of the SFF according to the forwarder registration message;

or

the SFF further comprising;

a deleting unit, configured to, receive an SF deregistration message; and

after receiving the SF deregistration message sent by the controller, delete a corresponding load balancing path and entries in a corresponding load balancing path table.

17. (canceled)

19. (canceled)

20. (canceled)

21. A classification device, comprising:

an encapsulating unit, configured to encapsulate a packet, wherein, to encapsulate a packet comprises addition of a Service Function Chain Flow Identifier, SFCFID, carried in a Service Function Chain, SFC, header corresponding to the packet; and

a sending unit, configured to send the encapsulated packet to a Service Function Forwarder, SFF.

22. The classification device according to claim 21, wherein the encapsulating unit comprises:

an SFCFID encapsulating module, configured to receive a load balancing path adding message sent by a controller, and during encapsulation of the packet, encapsulate the SFCFID in the SFC header corresponding to the packet according to the load balancing path adding message.

26. A Service Function Chain, SFC, system, comprising a controller, a Service Function, SF, entity, a classification device and a Service Function Forwarder, SFF, wherein

the classification device is the classification device according to claim 21, and the SFF is an SFF comprising:

a receiving unit, configured to receive a packet, wherein a Service Function Chain, SFC, header of the packet carries a Service Function Chain Flow Identifier, SFCFID; and

a forwarding unit, configured to forward the packet in a load balancing path according to the SFCFID carried in the SFC header of the packet.

23. (canceled)

24. (canceled)

25. (canceled)