Propagating a flow policy by control packet in a software defined network (SDN) based network

1. A method, comprising:

receiving, from a first forwarding node of a software defined network, a route path request for a flow;

responsive to the route path request, determining route path information specifying a route path for the flow using a processor of a software defined network controller; and

communicating the route path information from the software defined network controller only to the first forwarding node,

wherein the route path information is adapted to be used by the first forwarding node to generate a control packet comprising the route path, the control packet to be communicated to a second forwarding node of the route path;

wherein the second forwarding node comprises a flow table and, responsive to receiving the control packet, the second forwarding node updates the flow table according to the control packet, and

wherein the second forwarding node modifies the control packet for sending to a third forwarding node of the route path and sends the control packet to the third forwarding node.

2. The method of claim 1 , wherein the route path request specifies a start node and an end node.

3. The method of claim 1 , wherein the route path information further specifies a service to be applied to the flow.

4. The method of claim 1 , wherein the control packet is communicated from the first forwarding node to the second forwarding node using a data plane of the software defined network without intervention from the software defined network controller.

5. The method of claim 4 , wherein the first forwarding node sends the control packet to the second forwarding node prior to communicating any other packet of the flow to the second forwarding node.

6. A method, comprising:

sending a route path request for a flow from a first forwarding node to a software defined network controller of a software defined network;

receiving route path information specifying a route path for the flow from the software defined network controller;

generating, using a processor of the first forwarding node, a control packet comprising the route path; and

communicating the control packet from the first forwarding node to a second forwarding node;

wherein the second forwarding node comprises a flow table and, responsive to receiving the control packet, the second forwarding node updates the flow table according to the control packet, and

wherein the second forwarding node modifies the control packet for sending to a third forwarding node of the route path and sends the control packet to the third forwarding node.

7. The method of claim 6 , wherein the control packet is communicated from the first forwarding node to the second forwarding node over a data plane of the software defined network without intervention from the software defined network controller.

8. The method of claim 6 , wherein the control packet is sent from the first forwarding node to the second forwarding node prior to communicating any other packet of the flow to the second forwarding node.

9. The method of claim 6 , wherein the first forwarding node comprises a flow table and, responsive to receiving the route path information, updates the flow table; and

wherein the first forwarding node processes a data packet of the flow according to the updated flow table.

10. A system, comprising:

a processor programmed to initiate executable operations comprising:

sending a route path request for a flow from a first forwarding node to a software defined network controller of a software defined network;

receiving route path information specifying a route path for the flow from the software defined network controller;

generating a control packet comprising the route path; and

communicating the control packet from the first forwarding node to a second forwarding node;

wherein the second forwarding node comprises a flow table and, responsive to receiving the control packet, the second forwarding node updates the flow table according to the control packet, and

wherein the second forwarding node modifies the control packet for sending to a third forwarding node of the route path and sends the control packet to the third forwarding node.

11. The system of claim 10 , wherein the control packet is communicated from the first forwarding node to the second forwarding node over a data plane of the software defined network without intervention from the software defined network controller.

12. The system of claim 10 , wherein the control packet is sent from the first forwarding node to the second forwarding node prior to communicating any other packet of the flow to the second forwarding node.

13. The system of claim 10 , wherein the first forwarding node comprises a flow table and, responsive to receiving the route path information, updates the flow table; and

wherein the first forwarding node processes a data packet of the flow according to the updated flow table.

14. A non-transitory computer program product comprising a computer readable storage medium having program code stored thereon, the program code executable by a processor to perform a method comprising:

sending a route path request for a flow from a first forwarding node to a software defined network controller of a software defined network using a processor of the first forwarding node;

receiving route path information specifying a route path for the flow from the software defined network controller using the processor of the first forwarding node;

generating a control packet comprising the route path using the processor of the first forwarding node; and

communicating the control packet from the first forwarding node to a second forwarding node using the processor of the first forwarding node;

wherein the second forwarding node comprises a flow table and, responsive to receiving the control packet, the second forwarding node updates the flow table according to the control packet, and

wherein the second forwarding node modifies the control packet for sending to a third forwarding node of the route path and sends the control packet to the third forwarding node.

15. The computer program product of claim 14 , wherein the control packet is communicated from the first forwarding node to the second forwarding node over a data plane of the software defined network without intervention from the software defined network controller.

16. The computer program product of claim 14 , wherein the control packet is sent from the first forwarding node to the second forwarding node prior to communicating any other packet of the flow to the second forwarding node.

17. The computer program product of claim 14 , wherein the first forwarding node comprises a flow table and, responsive to receiving the route path information, updates the flow table; and

wherein the first forwarding node processes a data packet of the flow according to the updated flow table.