It is interesting to see what the technologies and trends are when looking at what everyone is talking about at Mobile World Congress. I have had the opportunity to walk around the exhibits and talk to many equipment manufacturers, solution providers, and communications service providers (CSPs). Often, during my discussions, I end up comparing notes with my counterpart around Software-Defined Networking (SDN) and Network Functions Virtualization (NFV).
SDN? NFV? What Do They Mean?
These are very hot topics to discuss and everyone wants to be part of this movement. The problem is that every person I talk to has a different definition of what SDN and NFV are. The general concept behind SDN is that the businesses want to reduce their costs while creating a more flexible and dynamic network infrastructure at the same time. One way they can do this by separating the control plane from the forwarding plane in the network switches. The control plane can be centralized and run on general purpose servers and hardware. In addition, the network forwarding elements can start to become generalized commodities, not requiring vendor-specific technologies and be built from off the shelf components. Note that many discussions around SDN tend to focus on the abstraction of the control and data forwarding planes at the Layer 2 and 3 levels in the OSI model.
NFV is an offshoot of SDN created as a working group within European Telecommunications Standards Institute (ETSI) by many of the major CSPs. NFV is designed to be complementary to SDN. It is centered on the virtualization of network functions onto industry standard high performance hardware including servers, switches, and storage. Both the SDN and NFV concept are designed to reduce costs, improve speed of time to market by creating a flexible framework to add services and functions, and create a more open environment encouraging innovation.
One of the primary goals of both of these technologies is to build a flexible, cost effective, and common framework to deliver applications to the customers reliably. The framework must be flexible as new features and services are added, and adapt to change rapidly and easily from a network topology and management perspective. The framework must be dynamic to be able to handle changes in the network (component failures, network path changes) as well as changes in the traffic patterns seen on the data plane.
It’s All About the Application
By focusing on the delivery of applications and services, we are evolving the definition of SDN and NFV from developing solutions that focus on the data path to solutions that are concerned about data delivery. The delivery of this model can only be successful with the use of a common hardware framework that multiple applications can leverage through software virtualization. It is essential to provide a management and orchestration interface in order to automate key functions including making application resources available on demand.
This is what can be called Application Defined Networking (ADN). ADN focuses on the ensuring that the client is able to access the application. This can require subscriber identification, content and application analysis, application resource availability, and the identification of the path and application instance to deliver the best Quality of Experience (QoE) for the client. Networks care about packets. People care about applications. By focusing on the delivery of the application, we are able to abstract and virtualize the underlying network infrastructure enabling the benefits that the SDN and NFV are promoting.