The promise of software-defined networking — namely simpler, more flexible network operation through centralized, software-driven control — has been tangible for a few years now, though like many new concepts, it has suffered from misunderstandings and confusion due to amorphous definitions thrust upon it by eager marketing teams. On top of the many definitions, we’ve also seen a number of different approaches, with the OpenFlow model leading the way from the beginning.
Leave it to Cisco to come up with yet another way of doing SDN. Cisco’s Application Centric Infrastructure (ACI) is an SDN solution at odds with the OpenFlow approach, and as such, it diverges from the original direction of the OpenDaylight SDN project, of which Cisco is a founding member. Cisco continues to be a large presence in the OpenDaylight initiative, but is clearly favoring its own technology with ACI.