Software Defined Networking (SDN) has moved well beyond its initial use case within the data centre where it has become the preferred choice for a dynamic cloud environment. Its use has now moved outside the data centre and into the WAN in what is referred to as SD-WAN.
SD-WAN is increasingly popular with network service providers, especially those that are looking to replace or improve on traditional VPN services with a secure automated connectivity model, one that is able to work comfortably on any access network, whether MPLS, Internet or mobile.
“SDN makes a network more agile and dynamic,” believes Sunil Khandekar, founder and CEO of Nuage Networks, part of Nokia and a provider of open cloud networking and automation solutions for enterprises and service providers. “Benefits include simplified operations, real time network responsiveness, reduced network complexity and the ability to create new service offerings quickly and offer them as on-demand services to the end-user. This results in savings in operational and capital expenditure, as well as higher top line growth via new services that can now be deployed faster regardless of where and how an end-user is connected.”
The rise of SDN has coincided with an increase in the number of players in the market offering SDN and SD-WAN solutions. Service providers can choose from traditional network equipment vendors to startups to enterprise software companies. Everyone is selling the benefits of their approach and promising a new dawn. Navigating this labyrinth can be a challenging exercise for any enterprise or service provider looking to adopt SDN.
So what are the key considerations when selecting an SDN offer that will stand the test of time, not just from a technology, but also from an operational and TCO perspective? Khandekar proposes four tests that service providers should apply to distinguish different SDN offerings:
“They need firstly to be sure they are investing in a platform, rather than just a single point solution,” he advises. “The applicability of SDN spans network domains from DC to WAN to IoT to security and from virtual end points to physical switches. While your requirements today reflect your most pressing need in a single area, it is more than likely that your use cases will expand across domains over time.”
Next, service providers must prioritise service assurance and traffic insight: “The promise of SDN is built upon abstractions that hide underlying physical device and physical network complexity,” says Khandekar. “This is fabulous when the network is working as desired. But as soon as a there is a network break or failure, you need to be able to drill into the physical level to isolate faults and correlate physical layer errors to virtual network failures.”
A third priority must be openness and extensibility: “In the vendor community, it is a cliché to claim that a SDN solution is open,” he warns. “But what does this openness mean and what type of openness should an end user or customer care about? From a user perspective, the type of openness that matters the most is the ability to utilise the SDN solution with a diverse set of multi-vendor environments and use cases and avoid proprietary lock-ins.”
And finally, service providers must set value by the service and support that a vendor provides, for it is this that turns a simple proof of concept into a full-blooded commercial deployment.
“The move to SDN is more than a technology transition,” says Khandekar. “It involves organisational and skillset transformation along with a well-defined and focused business case. A successful transition to a real deployment requires varying degrees of consulting services, solution design and resident engineer support, as well as training and certification for employees.”
These four vendor attributes should ensure that the right SDN solution will support current and future business goals, and that SDN is not limited to a single area of the network. In this way too, the service provider’s customer is assured of the performance that they need to base their business success on.
“The ultimate Holy Grail is an AWS-like experience where the user can consume quickly and then move on,” concludes Khandekar. “Complexity must be abstracted away. You want to reduce friction for those who are consuming your networking, to deploy with minimal opposition. To this end, at Nuage Networks we do not require that the customer adopt any particular switch or router. You can deploy us today over any physical network. True openness is what’s needed. Don’t be limited by a particular appliance form or appliance vendor. Whatever you deploy must meet your needs today and in the long haul.”