Segment routing based wide area network orchestration in a network environment

1. A method, comprising:

monitoring a segment routing (SR) enabled wide area network (WAN) environment in real-time by a path computation element (PCE) located outside the WAN;

receiving an event notification at the PCE; and

performing traffic engineering using SR to reroute traffic off shortest paths, comprising a route optimization including:

minimizing a maximum violation of a preconfigured policy;

minimizing a total number of policy violations;

minimizing an amount of traffic off shortest Interior Gateway Protocol (IGP) path;

minimizing amount of state created;

limiting a number of segments used in the rerouting;

setting a delay bound per demand;

maximizing survivability; and

distributing traffic using equal cost multi-path (ECMP).

2. The method of claim 1 , wherein the optimization is differentiated by Quality of Service (QoS) classes.

3. The method of claim 1 , further comprising estimating a computation time for optimizing placement of SR tunnels, wherein a specific solver is chosen for performing traffic engineering from a plurality of solvers based on the computation time and availability of a pre-computed solution.

4. The method of claim 1 , wherein a current state of the WAN is not pre-computed, wherein performing traffic engineering comprises:

optimizing routes to remove violation of any utilization policies;

deploying the optimized routes in the WAN;

re-optimizing routes for other parameters; and

further deploying the re-optimized routes in the WAN.

5. The method of claim 1 , wherein a current state of the WAN is not pre-computed, wherein performing traffic engineering comprises:

optimizing routes to remove violation of any utilization policies and for other parameters; and

deploying the optimized routes in the WAN.

6. The method of claim 1 , wherein a current state of the WAN is pre-computed, wherein performing traffic engineering comprises:

deploying the optimized routes in the WAN; and

pre-computing additional failure scenarios, and clearance of the failure scenarios.

7. The method of claim 1 , wherein the traffic engineering is performed at a SR solver executing in the PCE.

8. The method of claim 1 , wherein the traffic engineering is performed at a SR solver executing in an off-line planning application, wherein the results of the SR solver are accessed by the PCE.

9. The method of claim 1 , wherein the monitoring is performed after predetermined time intervals.

10. Non-transitory tangible media that includes instructions for execution, which when executed by a processor, is operable to perform operations comprising:

monitoring a SR enabled WAN environment in at least near real-time by a PCE located outside the WAN;

receiving an event notification at the PCE; and

performing traffic engineering using SR to reroute traffic off shortest paths, comprising a route optimization including:

minimizing a maximum violation of a preconfigured policy;

minimizing a total number of policy violations;

minimizing an amount of traffic off shortest IGP path;

minimizing amount of state created;

limiting a number of segments used in the rerouting;

setting a delay bound per demand;

maximizing survivability; and

distributing traffic using ECMP.

11. The media of claim 10 , wherein a current state of the WAN is not pre-computed, wherein performing traffic engineering comprises:

optimizing routes to remove violation of any utilization policies;

deploying the optimized routes in the WAN;

re-optimizing routes for other parameters; and

further deploying the re-optimized routes in the WAN.

12. The media of claim 10 , wherein a current state of the WAN is not pre-computed, wherein performing traffic engineering comprises:

optimizing routes to remove violation of any utilization policies and for other parameters; and

deploying the optimized routes in the WAN.

13. The media of claim 10 , wherein a current state of the WAN is pre-computed, wherein performing traffic engineering comprises:

deploying the optimized routes in the WAN; and

pre-computing additional failure scenarios, and clearance of the failure scenarios.

14. An apparatus, comprising:

a PCE located outside a SR enabled WAN, wherein the PCE comprises a memory element for storing data and a processor, wherein the processor executes instructions associated with the data, wherein the processor and the memory element cooperate, such that the apparatus is configured for:

monitoring a SR enabled WAN environment in at least near real-time by the PCE;

receiving an event notification at the PCE; and

performing traffic engineering using SR to reroute traffic off shortest paths, comprising a route optimization including:

minimizing a maximum violation of a preconfigured policy;

minimizing a total number of policy violations;

minimizing an amount of traffic off shortest IGP path;

minimizing amount of state created;

limiting a number of segments used in the rerouting;

setting a delay bound per demand;

maximizing survivability; and

distributing traffic using ECMP.

15. The apparatus of claim 14 , wherein a current state of the WAN is not pre-computed, wherein performing traffic engineering comprises:

optimizing routes to remove violation of any utilization policies;

deploying the optimized routes in the WAN;

re-optimizing routes for other parameters; and

further deploying the re-optimized routes in the WAN.

16. The apparatus of claim 14 , wherein a current state of the WAN is not pre-computed, wherein performing traffic engineering comprises:

optimizing routes to remove violation of any utilization policies and for other parameters; and

deploying the optimized routes in the WAN.

17. The apparatus of claim 14 , wherein a current state of the WAN is pre-computed, wherein performing traffic engineering comprises:

deploying the optimized routes in the WAN; and

pre-computing additional failure scenarios, and clearance of the failure scenarios.