Method and apparatus for reflecting forwarding plane utilization in control plane

1. A method comprising:

setting a first oversubscription factor of a control plane for an interface;

measuring forwarding plane utilization on the interface;

calculating a second oversubscription factor of the control plane for the interface using the measured forwarding plane utilization as compared with a target forwarding plane utilization on the interface;

determining whether to update the first oversubscription factor based upon the calculated second oversubscription factor;

updating the first oversubscription factor to a new oversubscription factor; and

changing an advertised bandwidth of the control plane based upon the updating of the first oversubscription factor to the new oversubscription factor.

2. A method of claim 1 , wherein the first oversubscription factor is an initial oversubscription factor that is set based upon historical data of the control plane for the interface.

3. A method of claim 1 , wherein the new oversubscription factor is equal to a predetermined minimum oversubscription factor when the second oversubscription factor is less than the predetermined minimum oversubscription factor.

4. A method of claim 1 , wherein the new oversubscription factor is equal to a predetermined maximum oversubscription factor when the second oversubscription factor is greater than the predetermined maximum oversubscription factor.

5. A method of claim 1 , wherein the new oversubscription factor is equal to an initial oversubscription factor that is set based upon historical data of the control plane for the interface when a signaled bandwidth of the control plane for the interface is less than a predetermined threshold bandwidth.

6. A method of claim 1 , wherein the new oversubscription factor is equal to an initial oversubscription factor that is set based upon historical data of the control plane for the interface when a measured bandwidth of the forwarding plane is less than a predetermined threshold bandwidth.

7. A method of claim 1 , wherein the new oversubscription factor is equal to a signaled bandwidth of the control plane for the interface divided by a bandwidth of the interface when the calculated second oversubscription factor is less than the signaled bandwidth of the control plane for the interface divided by the bandwidth of the interface.

8. A method claim 1 , comprising:

setting a first oversubscription factor of a control plane for an interface;

measuring forwarding plane utilization on the interface;

calculating a second oversubscription factor of the control plane for the interface using the measured forwarding plane utilization as compared with a target forwarding plane utilization on the interface; and

determining whether to update the first oversubscription factor based upon the calculated second oversubscription factor,

wherein the first oversubscription factor is not updated when an absolute value of a percentage change between the first oversubscription factor and the calculated second oversubscription factor is less than a predetermined percentage change value.

9. A method comprising:

setting a first oversubscription factor of a control plane for an interface;

measuring forwarding plane utilization on the interface;

calculating a second oversubscription factor of the control plane for the interface using the measured forwarding plane utilization as compared with a target forwarding plane utilization on the interface;

determining whether to update the first oversubscription factor based upon the calculated second oversubscription factor; and

performing a plurality of measurements of forwarding plane utilization on the interface and calculating a plurality of second oversubscription factors of the control plane for the interface using respective measurements of forwarding plane utilization as compared with the target forwarding plane utilization on the interface,

wherein the determination of whether to update the first oversubscription factor is based upon an average of the calculated plurality of second oversubscription factors.

10. A method of claim 9 , wherein the determination of whether to update the first oversubscription factor is performed if a succession of consecutive calculated second oversubscription factors that are greater than the first oversubscription factor occur during an increase interval, and if a succession of consecutive calculated second oversubscription factors that are less than the first oversubscription factor occur during a decrease interval.

11. A method of claim 10 , wherein the decrease interval is shorter than the increase interval.

12. An apparatus comprising:

a control plane configured to set a first oversubscription factor for an interface;

a forwarding plane configured to grant access to the interface from one or more routers via the control plane,

wherein the control plane is configured to measure forwarding plane utilization on the interface, calculate a second oversubscription factor of the control plane for the interface using the measured forwarding plane utilization as compared with a target forwarding plane utilization on the interface, and determine whether to update the first oversubscription factor based upon the calculated second oversubscription factor,

wherein the control plane is further configured to update the first oversubscription factor to a new oversubscription factor, and to change an advertised bandwidth of the control plane based upon the updating of the first oversubscription factor to the new oversubscription factor.

13. A apparatus of claim 12 , wherein the forwarding plane is further configured to grant access to the interface via one or more additional control planes.

14. A apparatus of claim 12 , wherein the first oversubscription factor is an initial oversubscription factor that is set based upon historical data of the control plane for the interface.

15. A apparatus comprising:

a control plane configured to set a first oversubscription factor for an interface;

a forwarding plane configured to grant access to the interface from one or more routers via the control plane,

wherein the control plane is configured to measure forwarding plane utilization on the interface, calculate a second oversubscription factor of the control plane for the interface using the measured forwarding plane utilization as compared with a target forwarding plane utilization on the interface, and determine whether to update the first oversubscription factor based upon the calculated second oversubscription factor,

wherein the first oversubscription factor is not updated when an absolute value of a percentage change between the first oversubscription factor and the calculated second oversubscription factor is less than a predetermined percentage change value.

16. A apparatus comprising:

a control plane configured to set a first oversubscription factor for an interface;

a forwarding plane configured to grant access to the interface from one or more routers via the control plane,

wherein the control plane is configured to measure forwarding plane utilization on the interface, calculate a second oversubscription factor of the control plane for the interface using the measured forwarding plane utilization as compared with a target forwarding plane utilization on the interface, and determine whether to update the first oversubscription factor based upon the calculated second oversubscription factor,

wherein the control plane is further configured to perform a plurality of measurements of forwarding plane utilization on the interface and calculate a plurality of second oversubscription factors of the control plane for the interface using respective measurements of forwarding plane utilization as compared with the target forwarding plane utilization on the interface, and wherein the determination of whether to update the first oversubscription factor is based upon an average of the calculated plurality of second oversubscription factors.

17. A apparatus of claim 16 , wherein the determination of whether to update the first oversubscription factor is performed if a succession of consecutive calculated second oversubscription factors that are greater than the first oversubscription factor occur during an increase interval, and if a succession of consecutive calculated second oversubscription factors that are less than the first oversubscription factor occur during a decrease interval.

18. A apparatus of claim 17 , wherein the decrease interval is shorter than the increase interval.

19. A apparatus of claim 17 , wherein the routers include a logical router.