The Many Sides of Virtual Networking
SDN and NFV aren't mutually exclusive and the enterprise data center will eventually need both, but the differences between them still pose difficult choices.
With two predominant forms of network virtualization on the rise these days – software defined networking (SDN) and network functions virtualization (NFV) – it is understandable that confusion has arisen about how to deploy them across enterprise infrastructure.
Ideally, a single virtual format would extend across on-prem, interconnect, and cloud-based infrastructure, but the fact is that SDN and NFV bring unique capabilities to the table and therefore should be deployed according to a variety of factors, such as workload and user requirements.
The primary difference between the two lies in how they abstract network architectures on top of physical hardware, says Data Center Knowledge’s Bill Kleyman. SDN separates the control plane from the data plane, enabling a high degree of programmability that simplifies traffic management and enables broad automation across disparate, although usually open, network topologies. NFV more closely resembles traditional server virtualization, in which network services like load balancing, firewall management, and network acceleration reside on a virtual framework rather than in software sitting on bare metal.
There is no reason why the two cannot be deployed in conjunction, of course. In fact, this is the best way to achieve broad scalability and extensibility with sophisticated management and orchestration.
At the moment, most organizations are in need of scalability as they prepare for Big Data and the Internet of Things, according to VPS Hosting in an un-bylined editorial. That means NFV coupled with open cloud solutions like OpenStack will likely prove to be the bigger draw as more workloads migrate away from legacy data center infrastructure. Ultimately, however, it is reasonable to assume that all virtualized network architectures, including NFV, will be subsumed under an SDN paradigm that pushes network programmability, and thus the virtual or software defined data center (SDDC), across distributed infrastructure that could stretch around the world, or beyond.
But if NFV is the immediate goal and SDN is more suitable for long-term planning, someone forget to tell the enterprise. According to the latest poll by Enterprise Networking Planet parent company Quinstreet, nearly 40 percent of organizations are either using SDN now or are planning to roll it out over the coming year. That number jumps to almost half when a two-year timeframe is contemplated. To be sure, enterprise executives are weighing an array of virtual networking options, including NFV and VLANs, but in terms of flexibility, cost savings and improved productivity throughout the entire data stack, SDN is seen as the next big growth area.
All of this may prove to be a distinction without a difference in the end. Software defined networking will most likely be deployed within the data center, while NFV will handle the connectivity between data centers, either in the cloud or in more traditional colocation settings. This is being seen in the data center interconnect (DCI) industry as companies like Adva Optical build NFV capabilities into their software portfolios. The company recently purchased Overture Networks, which specializes in Ethernet-based virtual networking, and plans to leverage its NFV products for a new division called Ensemble. The idea is to allow SDN and NFV to inhabit the metro service edge, giving enterprises and service providers alike the ability to integrate local and wide area connectivity on a virtual plane while still providing backward connectivity to legacy Ethernet protocols. (Disclosure: I provide writing services to Adva Optical).
For a while, then, it appeared as if the enterprise faced a stark choice between SDN and NFV, but fortunately this is not the case. Both technologies will coexist within a distributed data environment to provide the services needed to support full virtualized information infrastructure in both local and long-haul settings.
This isn’t to say that integration, interoperability and overall orchestration will be a cakewalk, but at least the networking side of the emerging virtual data environment is not facing yet another format war.
Arthur Cole covers networking and the data center for IT Business Edge. He has served as editor of numerous publications covering everything from audio/video production and distribution, multimedia and the Internet to video gaming.