How do we define software defined networking? At the most basic level any networking infrastructure that has the ability to be programmed is ‘software defined’. Being able to dynamically react to changing conditions in the environment and to the needs of users is at the core of this movement. That said, how do you know where to begin or where is this technology being used today? In order to stay ahead of the curve, you need to know where it is, and where it’s going.
Truth be told, networks have been software defined for a long time – it’s the extent to which they are programmed and automated that is significant in this era of networking. What we are really looking at is intelligent and self-automated networks, which is to say little to no human intervention is required to allow them to adapt to changing conditions.
What are the most practical use cases today for SDN?
As with most emerging technologies, the majority of companies are not yet adopting the complete SDN portfolio but have identified targeted applications of SDN that can solve immediate challenges. For many companies, SDN initiatives have been focused on SD-WAN (Software Defined Wide Area Network).
Historically companies have deployed redundant infrastructure to eliminate single points of failure in mission-critical connections between network nodes. Similar to an insurance plan, this additional infrastructure (hardware, circuits, etc) often remains completely unused until a failure occurs - yet the company pays to have it available all the time. SD-WAN, leveraging programmatic ‘intelligence’ within the wide area network, allows companies to utilize the redundant infrastructure all the time. No longer an ‘insurance policy’ infrastructure investment that a company pays for while hoping to never use, the intelligent SD-WAN uses all available infrastructure all the time. SD-WAN automation determines how best to distribute network traffic across all available paths, monitors the performance of each path in real time, and dynamically reacts to service degradation or failures in order to maintain the level of network availability the company invested in to begin with.
What are early adopters doing with this technology?
Google, Facebook, and Uber are examples of companies that are leading the adoption of new technologies to support their businesses. Having to deal with drastically changing levels of customer traffic on a daily basis, they are using SDN to create a more flexible and dynamic network that can scale up or down in response to changes in demand. Being able to bring more compute and communications resources online to respond to a surge in customer activity or, likewise, being able to spin down resources and reduce operating costs when customer activity lulls – all without any human intervention - is the real benefit of SDN. Companies are no longer forced to bear the costs of a network that supports ‘peak’ levels of activity 100% of the time when ‘peak’ levels of activity actually occur far less frequently.
What are the limitations right now and why aren't SMBs doing more?
Many of the more ‘exciting’ or innovative applications of SDN are bleeding-edge and have not proven themselves in widespread enterprise deployments, and some SDN components are open source projects in a constant state of change. Many businesses will not assume the risk of being early adopters of new products. SDN implementations can also force an initial investment in costly new hardware that supports the level of programmability required by SDN. And there are also education requirements in that SDN can, in some ways, force ‘network’ staff to become ‘programmers’ to some extent.
Enterprise adoption of SDN will increase in coming years as the technology matures and proves itself.