Software-defined networking has tremendous potential to transform all data networking due to its ability to separate network control from packet delivery. But most organizations are currently focused on what SDN can do for them in the data center. On one hand, by making the network completely programmable, SDN promises to make the network as agile and automated as virtual servers and storage, which makes the data center function more like a cloud. On the other hand, through microsegmentation, SDN offers a more flexible and manageable technology for improving the data center security landscape.
Given all that, and the fact that SDN has been talked about in one way or another for five years or more, fewer than 10% of organizations have deployed data center SDN in production. It turns out that even as technologies have matured to the point where they are stable and scalable enough to serve, they are not yet easy to deploy, or at least not easy enough for broad and deep deployment.
Early adopters tell similar stories. They say it's possible to achieve what they were hoping for in terms of simplification, but that success requires a lot of hard work. The hard work comes in terms of thoroughly mapping out the web of relationships in the data center to understand how to segment the network properly. In production, complexity also comes in terms of manually building out the security groups and policies and knitting together the various tools required to provide true cloud-like behavior.
Cloud management, data center SDN as internal cloud pieces
For enterprises that want to build a true private cloud, the data center SDN issues are only one facet of the larger question of how to justify it. Anyone committed to the effort must make a hard calculation. Organizations have to decide whether the effort involved in creating a private cloud using virtualization, SDN and a cloud management platform is worth the investment. To make it work for the organization, they either must buy or build layers of low-level building blocks that include virtual servers of various sorts, virtual storage services and networking.
They will also have to develop or acquire middleware functions: an internal platform as a service of various sorts to provide database services and application services with load balancing and redundancy. Then they must bring it all together in a portal and catalog, with appropriate accounting to prevent re-enacting the tragedy of the commons with their resource pools. Then, of course, they must provide the orchestration layer to make it responsive to changes in demand and load.
Even with a cloud management platform, it takes a lot of layers of effort and the significant burden of systems integration. For some organizations, there's no question that the effort is worth the reward. For others, using a public cloud is not an option as a matter of policy.
For those who can, the alternative is to make use of public cloud offerings, or cloud services. Amazon, Microsoft, Google, IBM, Oracle and others have already done the low-level work -- and in varying degrees, the middle-level work as well -- and they are providing much of the necessary orchestration behind the scenes.
Given the fact that 75% of organizations make some use of infrastructure as a service already, for example, can they justify the effort of deploying an internal cloud at this point? Is it worth it to them to recreate the engineering effort of developing a scalable, resilient database service given that so many cloud service providers already have? On careful examination, they will more than likely find that sticking with virtualized but not fully "cloudified" operations in their own data centers while expanding use of the public cloud makes more sense, at least until building a private cloud using a cloud manager and data center SDN and all the rest, is much simpler.
Private cloud architecture can be enabled by SDN
How microsegmentation helps lock down software-defined network security
SDN can open up your private cloud network bottleneck