The Point of Software Defined Networking

Carole Warner Reece

I’ve been thinking about many of the topics that were discussed in the recent Software Defined Data Center (SDDC) Symposium and Networking Field Day (NFD6) meetings I attended last month.

What really stands out for me is that the use case for Software Defined Networking (SDN) is extremely compelling – simplistically stated, SDN is the ability to simplify network operation through automation. But that is not the complete story — SDN provides an opportunity to make the network more transparent, applications more visible, and business requirements more integrated.

Nuage Networks talked about SDN and the importance of abstractions. For example, the abstraction of a network service such as a firewall would be the templates that set policy and resources for the firewall. The network administrator would design and configure the service template, and the users would just permitted or denied access to resources based on the firwall policies.

However, in the near term SDN abstraction of services and network automation simply will not be available pervasively across an organization. So a good question is where can SDN be effectively applied now, is it data centers or the enterprise or with service providers or someplace else?

Many of my customers are enterprise based. They are looking to reduce operational risk (of moves and changes) while supporting business agility. For the enterprise user, I see a couple of questions:

  • What is the timeframe for SDN for the enterprise when they already have an installed base of network gear?
  • Can they connect new SDN technology to existing legacy systems and achieve business benefits?
  • Will the technology threaten people’s jobs? (If so, it will be very hard to bring it into enterprise.)

One underlying IT issue is that compute / storage / network connectivity / network services are often very separate groups in an organization. A specific technology such as SDN is not going to resolve organizational processes or operational issues between separate groups.

Several aspects of cloud based computing have made the SDDC the best fit for the initial focus of SDN:

  • Cloud based computing is an environment where multiple organizations are using shared resources. (They are using the cloud to reduce operational costs/risks and to provide business agility.)
  • The cloud service provider is a new organization. Their business processes have not been entrenched for years.
  • Cloud computing can include compute, storage, and network services. The details of cloud computing are hidden from the end user. The end user just needs to attach to it, and they do not have to completely change their existing business processes to use them.
  • Policy management can centralized to a cloud. For the emerging SDN tools, centralized control is quite helpful. Templates can be centrally developed for the cloud environment, and then applied to diverse user groups.

One speaker from Plexxi said that SDDC can provide a system level perspective of the network based on business requirements.

Will SDN investments meet ROI requirements? Maybe not initially, but eventually SDN will help us model applications across entire system. It will make networks more agile and responsive to business requirements. SDN will make the business perform better when the network is better supporting the applications. I’m looking forward to deploying it.

— cwr

Twitter: @cwreece



This is my first article reviewing the technologies and discussions from NFD6. The Networking Tech Field Day events are organized by Gestalt IT who also select the delegates. Gestalt IT covered most of my travel expenses. (Thanks again Stephen, Tom, and Claire for both putting together the event and inviting me to participate!)

These events are sponsored by networking vendors who therefore indirectly cover the NFD delegate’s travel expenses. In addition to a presentation, vendors may give the delegates shirts, pens, or other promotional items. The vendors sponsoring Tech Field Day events do not ask for, nor are they promised any kind of consideration in articles or blogs by delegates. The time spent in presentations and discussion does get me and the other delegate looking at and thinking about the various vendors’ products, marketing spin, and their points of view. I intend to remain as objective as possible, and all opinions expressed here are my own and not those of sponsoring vendors or my employer.

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Nick Kelly

Cybersecurity Engineer, Cisco

Nick has over 20 years of experience in Security Operations and Security Sales. He is an avid student of cybersecurity and regularly engages with the Infosec community at events like BSides, RVASec, Derbycon and more. The son of an FBI forensics director, Nick holds a B.S. in Criminal Justice and is one of Cisco’s Fire Jumper Elite members. When he’s not working, he writes cyberpunk and punches aliens on his Playstation.


Virgilio “BONG” dela Cruz Jr.

CCDP, CCNA V, CCNP, Cisco IPS Express Security for AM/EE
Field Solutions Architect, Tech Data

Virgilio “Bong” has sixteen years of professional experience in IT industry from academe, technical and customer support, pre-sales, post sales, project management, training and enablement. He has worked in Cisco Technical Assistance Center (TAC) as a member of the WAN and LAN Switching team. Bong now works for Tech Data as the Field Solutions Architect with a focus on Cisco Security and holds a few Cisco certifications including Fire Jumper Elite.


John Cavanaugh

CCIE #1066, CCDE #20070002, CCAr
Chief Technology Officer, Practice Lead Security Services, NetCraftsmen

John is our CTO and the practice lead for a talented team of consultants focused on designing and delivering scalable and secure infrastructure solutions to customers across multiple industry verticals and technologies. Previously he has held several positions including Executive Director/Chief Architect for Global Network Services at JPMorgan Chase. In that capacity, he led a team managing network architecture and services.  Prior to his role at JPMorgan Chase, John was a Distinguished Engineer at Cisco working across a number of verticals including Higher Education, Finance, Retail, Government, and Health Care.

He is an expert in working with groups to identify business needs, and align technology strategies to enable business strategies, building in agility and scalability to allow for future changes. John is experienced in the architecture and design of highly available, secure, network infrastructure and data centers, and has worked on projects worldwide. He has worked in both the business and regulatory environments for the design and deployment of complex IT infrastructures.