Service chaining of virtual network functions in a cloud computing system

1. A method of provisioning a network service in a cloud computing system, comprising:

defining, at an orchestrator, the network service to include a plurality of network functions;

defining an order of the plurality of network functions of the network service;

defining, at the orchestrator, network connectivity among the plurality of network functions, wherein the network connectivity of the plurality of network functions is based on the order defined for the plurality of network functions of the network service, and wherein the connectivity includes layer-2 or layer-3 network connectivity between network functions;

defining a location of each network function of the network service;

identifying a plurality of vendor device managers (VDMs) configured to provision virtual network functions that implement the plurality of network functions, wherein the VDMs are identified based on the location of each network function of the network service; and

instructing, by the orchestrator, the VDMs to deploy the virtual network functions in the defined order of the plurality of network functions.

2. The method of claim 1 , wherein the orchestrator is configured to deploy a plurality of built-in virtual network functions, and wherein the method further comprises:

identifying at least one built-in virtual network function for implementing a respective at least one network function of the network service; and

identifying, at the orchestrator, additional network connectivity between the virtual network functions and the built-in virtual network functions.

3. The method of claim 2 , further comprising:

deploying, by the orchestrator, the at least one built-in virtual network function having the additional network connectivity.

4. The method of claim 1 , wherein the orchestrator is implemented in a first data center and each of the plurality of VDMs is implemented in an additional data center.

5. A non-transitory computer readable medium comprising instructions, which when executed in a computer system, causes the computer system to carry out a method of provisioning a network service in a cloud computing system, comprising:

defining, at an orchestrator, the network service to include a plurality of network functions;

defining an order of the plurality of network functions of the network service;

defining, at the orchestrator, network connectivity among the plurality of network functions, wherein the network connectivity of the plurality of network functions is based on the order defined for the plurality of network functions of the network service, and wherein the connectivity includes layer-2 or layer-3 network connectivity between network functions;

defining a location of each network function of the network service;

identifying a plurality of vendor device managers (VDMs) configured to provision virtual network functions that implement the plurality of network functions, wherein the VDMs are identified based on the location of each network function of the network service; and

instructing, by the orchestrator, the VDMs to deploy the virtual network functions in the defined order of the plurality of network functions.

6. The non-transitory computer readable medium of claim 5 , wherein the orchestrator is configured to deploy a plurality of built-in virtual network functions, and wherein the method further comprises:

identifying at least one built-in virtual network function for implementing a respective at least one network function of the network service; and

identifying, at the orchestrator, additional network connectivity between the virtual network functions and the built-in virtual network functions.

7. The non-transitory computer readable medium of claim 6 , further comprising:

deploying, by the orchestrator, the at least one built-in virtual network function having the additional network connectivity.

8. The non-transitory computer readable medium of claim 5 , wherein the orchestrator is implemented in a first data center and each of the plurality of VDMs is implemented in an additional data center.

9. A computing system, comprising:

a memory storing program code; and

a processor, coupled to the memory, configured to execute the program code to provision a network service in a cloud computing system by:

defining, at an orchestrator, the network service to include a plurality of network functions;

defining an order of the plurality of network functions of the network service;

defining, at the orchestrator, network connectivity among the plurality of network functions, wherein the network connectivity of the plurality of network functions is based on the order defined for the plurality of network functions of the network service, and wherein the connectivity includes layer-2 or layer-3 network connectivity between network functions;

defining a location of each network function of the network service;

identifying a plurality of vendor device managers (VDMs) configured to provision virtual network functions that implement the plurality of network functions, wherein the VDMs are identified based on the location of each network function of the network service; and

instructing, by the orchestrator, the VDMs to deploy the virtual network functions in the defined order of the plurality of network functions.

10. The computing system of claim 9 , wherein the orchestrator is configured to deploy a plurality of built-in virtual network functions, and wherein the processor is further configured to:

identify at least one built-in virtual network function for implementing a respective at least one network function of the network service; and

identify, at the orchestrator, additional network connectivity between the virtual network functions and the built-in virtual network functions.

11. The computing system of claim 10 , wherein the processor is further configured to:

deploy, by the orchestrator, the at least one built-in virtual network function having the additional network connectivity.