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Riverbed Technology 2013 Predictions: SDN jumps from hype to reality by addressing its biggest problem

VMblog Predictions

Virtualization and Cloud executives share their predictions for 2013.  Read them in this series exclusive.

Contributed article by Steve Riley, Technical Director in the Office of the CTO at Riverbed Technology

SDN jumps from hype to reality by addressing its biggest problem

In 2013, the software-defined network (SDN) conversation will shift away from moving bits around the lower layers of the network stack to managing complexity at the upper layers. This will help to create a bridge between the vision of what network virtualization is supposed to deliver and what is needed today to make that happen: network consistency. 

For the past year, network pundits obsessed about the transition to network virtualization and debated the merits of one tunneling protocol over another. While such nuts-and-bolts thinking  is necessary, we must continue to remember the goal: to solve difficult and challenging networking problems. Server virtualization-converting servers from silicon to software-provides useful operational capabilities. In addition, provisioning is nearly instantaneous, and snapshots and rollbacks are now simple scripts. Effective network virtualization-where the network is similarly a software entity-must provide similarly useful operational capabilities. When the control plane is decoupled from the physical network fabric and reconstituted as a collection of logical abstractions, many of the usual constraints (topology, connectivity, limited state awareness, the pain of renumbering) fade away.

Now that the SDN die has been cast, what will matter next is where the innovation lies.

As I described in a recent article, with SDN, the control plane is built with software running on ordinary server computers (while the forwarding plane continues to exist in hardware). One of the challenges of this is network consistency. Ensuring consistency requires a lot of intelligence because virtual networks need to know everything about all nodes and ports, make sure that all of the paths are consistent whenever it comes time to plumb a new connection, and do all of this very fast.

A battle is brewing over where these brains should go in an SDN, with various interests jockeying for "enhanced semi-standard" control plane implementations (sometimes implemented in dedicated hardware components!). Business wants the flexibility to program SDNs and, frankly, the market will determine how this will be offered - open-source or proprietary - it really doesn't matter.

But my belief is that software controllers are the key to a programmable infrastructure, and virtual networks constructed of such software will turn the cloud to the reality that we've wanted. It is hard work and scary-but necessary.

Programmability means that the internal application and network teams will have to collaborate and play in the same sandbox because application performance is no longer isolated from the network. These teams will need to work together in order to ensure the performance, control, and security of applications.

In addition, a self-service network development model will evolve with fully automated provisioning of cloud environments that enable enterprises to visualize and control their networks with their own tools. In essence, they'll "program" their network with their own parameters. It is the ultimate in flexibility and innovation as more enterprises realize that they can rapidly and dynamically carve up their network and data center as needed. By spooling up and down entire functional ensembles of servers and networking to meet changing business demands, SDN will offer up a level of flexibility and nimbleness that is not available with traditional networks and data centers.

This is the SDN conversation I look forward to having in 2013.


About the Author

Steve Riley is a Technical Director in the Office of the CTO at Riverbed Technology. His specialties include the performance and security aspects of enterprise and cloud computing. Steve has a long career of public speaking, having participated in hundreds of events around the world. He is co-author of Protect Your Windows Network, contributed a chapter to Auditing Cloud Computing, has published numerous articles, and conducted technical reviews of several data networking and telecommunications books. At Riverbed, Steve concentrates on high-performance architectures that span multiple clouds, public and private. Before Steve joined Riverbed, he was cloud security strategist at Amazon Web Services and a security consultant and advisor at Microsoft; in both capacities, he developed patterns and practices for secure deployments and operations. Steve is a member of the Kubuntu Team (which maintains Ubuntu's KDE-flavored distribution) and is a global moderator of its community forum. Besides lurking in the Internet's dark alleys and secret passages, he enjoys freely sharing his opinions about the intersection of technology and culture. Contact him at
Published Friday, January 04, 2013 5:08 PM by David Marshall
Comments - Virtualization Technology News and Information for Everyone - (Author's Link) - January 15, 2013 6:59 AM

First, I'd like to personally thank everyone for being a valued member and reader of VMblog! Once again, with the help of each of you, VMblog has been able to remain one of the oldest and most successful virtualization and cloud news sites on the Web

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