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Software Defined Networking: Trend or technology movement?

Will SDN be coming soon to a network near you?

SDN software defined networking questions
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Software-defined networking (SDN), and what it means for the industry, is continually changing. According to TechTarget, "The goal of SDN is to allow network engineers and administrators to respond quickly to changing business requirements." SDN provides the capabilities to shape traffic from a centralized console, bypassing the need to configure individual switches. This allows services to be delivered where they are needed, when they are needed – with less room for human error.

By definition, SDN seems like a no-brainer. It makes perfect sense for organizations to strive to quickly adapt to changing business requirements, so why not implement SDN tomorrow? Not so fast. We keep hearing about it, and more companies are working to gain a foothold in the SDN space, but is it right for the enterprise network right now? It depends. 

The Significance of SDN

Let's first answer the question: why do people care about SDN? It comes down to two fundamental reasons: one political, one technical. The political reason is due to the fact that some people do not agree with big manufacturers having so much control over their networks. With closed systems, your options are extremely limited based on the hardware and software the OEM provides, with little room for customization. So, why not cut the cord? The concept of SDN could provide the freedom from manufacturers that IT professionals have dreamed about for years. 

The second reason people care is purely technical. SDN became what it is today because there was a technical need for companies to build a new infrastructure design that effectively met their business needs. Companies like Google, Amazon, and Facebook, which are controlling more data flow than we could have ever imagined possible, were not able to handle the amount of traffic with the standard client/server architecture that most of us deploy today. The compute and storage capacity needed for these companies is enormous. According to Lee Doyle, principal analyst at Doyle Research, "Their data centers typically range in size from 250,000 to more than 500,000 square feet (larger than a typical Walmart store) and house 100,000 to 500,000+ physical servers."

To put this in perspective, Doyle notes that Google's centralized software control stack manages thousands of switches and treats them as one large fabric. That includes 100,000 servers in its network, exchanging information at 10Gbps within one data center. That marks a capacity increase of 100 times over the past few years. More than 100 times the capacity, managed with one centralized software control stack. To call it impressive isn't doing it justice.

SDN in the Mainstream

Extraordinary though it may be, there is still some doubt that SDN will become mainstream for the average IT professional. Gartner's 2015 Networking and Communications Hype Cycle places SDN at the trough of disillusionment, due to "the result of too much marketecture, and not enough real-world implementations." They estimate that there are fewer than 2,000 production SDN enterprise deployments. The Register says SDN has hit "rock bottom," and that "people for whom it has no appeal beyond marketing will give up and leave the technology for those that actually need it."

Is SDN right for your network? For most average-sized organizations, the answer is probably not yet. Is it something you should keep an eye on? Absolutely. For those of us who don't have the extreme volume of traffic like the Googles and Amazons of the world, this trend is just that for now – a trend.

While it may be a trend at the moment, there's no doubt it's making its mark on the industry. An IDC study forecasts the SDN market will reach more than $3.5 billion in revenues by next year. The main players are certainly taking notice. Just last year, former Cisco CEO John Chambers claimed victory in the company's battle with SDN with the increase in popularity of its Application-Centric Infrastructure (ACI), which it describes as a "business-relevant Software Defined Networking policy model." More manufacturers are coming on board to claim their stake in the market and to combat the Cisco giant. HP recently introduced a new line of open switches and expanded its partnership with VMware, which shows that it's taking the SDN game pretty seriously. 

Whether you fall into the political or technical train of thought in favor of SDN, or if you believe it's a trend that will only impact a small percentage of large-scale enterprises, SDN will likely end up benefitting us all in some way. Perhaps what will be most exciting about this technology is what comes out of it beyond the full one-size-fits-all SDN implementation. What pieces and parts will be developed and pave the way for certain capabilities to become widely used and interchanged? The automation of processes and zero-touch configuration is something we could all use to make our lives easier.

With any new technology initiative comes opportunity and innovation. There's no doubt the industry advances that come as a result of SDN will affect the enterprise network, even if full SDN implementations don't become as commonplace as some expect today.

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