When it comes to operator networks, user experience means a lot. The proliferation of mobile devices, the emergence of the Internet of Things (IoT) and the cloud continue to raise the user experience bar. Keeping up with customer demand and reducing interruptions forces operators to focus on implementing automation tools to minimize interruptions in Quality of Service (QoS).

Looking ahead to what is in store for networks and IoT, SDN is a viable solution to manage increased traffic and control QoS. We've already seen SDN change the data center network and now it is redefining other types of networks.

As a network architecture, SDN allows for network control to be decoupled from the forwarding plane. It also allows the forwarding plane to be directly programmed by the control plane. Mobile networks are strong candidates for SDN implementation as they already maintain a separation of the control and data planes. With SDN, enterprises and carriers gain vendor-independent control over the entire network from a single logical point, which greatly simplifies network design and operation. SDN allows IT to leverage simplified network design to deploy new services in a matter of hours or days, not weeks or months, and create new services for differentiation. SDN provides a flexible tool to improve network management. But SDN has another role too, and that is with applications.

An SDN application is a software program designed to perform a task in an SDN environment. These applications replace and expand current network functions that are delivered through firmware in the hardware devices of a conventional network. For operators, SDN applications really assist in managing network bandwidth and ultimately improve QoS. With the increase in connected devices, the industry's interest in the application of OpenFlow-based SDN technologies to wireless and mobile networks has increased significantly since the founding of the Open Networking Foundation (ONF) in 2011.

The ONF even developed its own open source network tapping application called SampleTap. It was built on OpenFlow, was written to run on an OpenDaylight controller, and was intended to be an educational resource for programmers. This application enabled network administrators to troubleshoot network flows and gain better visibility into networks. This allowed them to essentially "tap" into the network, diagnose any flow issues, and solve them accordingly. Again, SampleTap was created to be thought-provoking and serve as an educational tool, not a commercial solution.

SDN can make a huge impact on the user experience via applications that can be built upon its framework. Like consumer app stores for mobile devices, developers are now able to create applications that address myriad consumer needs. The apps used on mobile devices enable users to do things they couldn't do on previous iterations of these devices: SDN can have a similar impact when it comes to the networks. In an SDN-enabled network, service providers can create any number of applications that can cut their opex and capex, improve customer experience, and deliver new monetization opportunities, ultimately enhancing the network's overall business value.

When considering SDN applications, it is beneficial to consider self-optimizing networks. Organizations have long relied on technologies such as load balancers and mobile optimization; these were applied on a device-by-device level and not holistically. SDN enables IT managers to have a bird's-eye view of the entire network, allowing them to manage, route and prioritize network traffic effectively. Given that optimization can be done automatically via an application, self-organizing networks can turn the network overload into a balanced load, improving the quality of user experience.

To help promote the future of open SDN applications, ONF will host the organization's first AppFest, an event designed to encourage the future development and testing of open SDN applications. ONF AppFest 2015 allows us to accommodate the industry's changes, while encouraging those within to collaborate and develop open SDN applications for the betterment of the industry.

As SDN adoption continues to accelerate, we are seeing new and innovative ways networks are using SDN that will in turn provide a wealth of new networking applications. While SDN makes networks flexible and customizable, the applications provide service availability, bandwidth management, content caching, optimal QoS, energy saving, and more. At this point in SDN's evolution, it is clear that it is becoming a reality in operator networks. Outside of the immediate impacts SDN brings via simpler network management, SDN applications will be the real driving force, advancing the SDN movement further into an operator's network and business.

Network infrastructure vendors in particular need to begin adding SDN applications to their roadmap in order to harness their full potential. By thinking of these applications now, network infrastructure providers and operators will be able to rapidly evolve and provide customized, flexible networks that enhance the user experience and ultimately positively affect their bottom line.

— Dan Pitt, Executive Director, Open Networking Foundation