APPARATUS FOR HYBRID ROUTING IN SDN NETWORKS TO AVOID CONGESTION AND ACHIEVE GOOD LOAD BALANCING UNDER FLUCTUATING TRAFFIC LOAD

A controller having an application optimally routing traffic to balance fluctuating traffic loads in a SDN network. A processor is configured to control the data plane to establish routing through the plurality of routers, wherein the processor is configured to establish hybrid routing comprising both explicit routing and destination-based routing. The processor utilizes a set of traffic matrices representing the fluctuating traffic load over time. A destination-based multi-path routing algorithm is configured to improve load balancing of the traffic load based on the set of representative traffic matrices. The destination based routing is calculated based on linear programming. The processor comprises a traffic categorization algorithm configured to identify a set of key flows, wherein the processor is configured to explicitly route the set of key flows. The processor is configured such that the set of key flows consume a small fraction of a ternary content-addressable memory (TCAM), and such that the set of key flows provide a routing decision for a large portion of the traffic load.