There are many facets of Software Defined Networking (SDN) implementation. What exactly it means depends on the type of problem you try to solve.
Sebastian Graf, Solutions Architect at Xantaro, explains the advantages of Software Defined Networking from a technical perspective and gives an idea of the layered approach within the SDN architecture.
Part 2: SDN in the Data Centre & Juniper Networks Contrail Show Case
Part 3: Software Defined Networking in Wide Area Networks