SDN Is Changing Everything
The demand for SDN is being driven by major communications service providers and major enterprises, versus the network equipment manufacturers (NEMs). If you were a telecom service provider or other major consumer of network infrastructure equipment, SDN is in theory very attractive for various reasons, such as the ability to only wire your network once and only once and use centrally controlled, lower-cost switches from multiple vendors
SDN is still in "early adopter" stage but moving fast. Companies like Google and Amazon have proven out the concept. However, market requirements to support service providers and major enterprises are still evolving. What are the various use cases that need to be supported? What type of programmatic interfaces should be presented? What types of network applications need to be supported?