One of the biggest potential gains from implementing NFV and SDN orchestration is being able to reconcile equipment differences and promote interoperability in complex multi-vendor network environments. While Ethernet has long been the standard LAN technology for technology organizations, standardization of WANs has taken longer and left much to be desired in terms of data transmission rates, cost-effectiveness and support for mixed workloads and infrastructure. An NFV-SDN combination may provide a way forward.
Using software-defined networking and network functions virtualization for interoperability
First, it's important to delineate the differences between NFV and SDN, since the terms are often conflated.
Strictly speaking, a software-defined network is one in which the data plane and control plane are separated, and which the control plane is managed by centralized software running on a standard server rather than distributed across network devices. This allows software-defined networks to be highly automated, and together with open protocols like OpenFlow, SDN can provide much more flexibility and economy than strictly hardware-based networking.
NFV migrates network services such as load balancing and intrusion prevention system management away from dedicated hardware and into virtualized environments. It is possible to implement NFV without SDN, but the benefits of NFV can be more effectively realized when used in tandem with SDN. Often leveraging the intelligence of an SDN controller, NFV activities can be managed in accordance with network state and demand. Servers can be spun up, new instances can be initiated and network services and application can be deployed as conditions change.
More on NFV and SDN together
In theory, an ideal SDN/NFV setup will allow replacing specialized network components with more generic equipment, which means that the infrastructure interoperability problems that have plagued technology organizations and service providers in the past can be more easily overcome. However, in practice, it's not always that simple.
For example, vendors like Cisco have promoted visions of "SDN" that are still hardware-reliant. Furthermore, the software based centralized controllers driving SDN networks can often introduce additional latency and delays that can cripple time critical networks.
NFV can help here by consolidating many functions into virtual workloads running on commodity servers. With the ability to easily move network functions between virtual machines, an SDN/NFV network can optimize to reduce issues like latency. In addition, differences at the physical level can be put aside and the network can become much more scalable and flexible. With the right NFV orchestration platform, there is great potential for OPEX and CAPEX savings, even if an organization has to deal with large amounts of legacy infrastructure on the ground.
Where to start with NFV and SDN?
Data centers have been at the center of most discussions of NFV and SDN. Most of the benefits and key challenges discussed above pertain to remaking the networks at these facilities. However, the benefits of combining SDN and NFV can also be a good fit for WANs.
Speaking to Network World, Michael Elmore, an IT executive at Cigna and a board member at the Open Network Users Group, stated that software-defined WANs were attracting a lot of interest on Wall Street. Moreover, SD-WAN could save firms money on bandwidth compared to MPLS and streamline CAPEX and OPEX, much like the NFV-SDN pairing can do in the data center.
SDN's effects on WANs may be worth keeping an eye on in light of the incremental progress of NFV and SDN adoption so far. Potential is high, but many teams are still looking for practical use cases as well as feasible ways to transition from their current environments.
The takeaway: NFV and SDN together can address the interoperability issues that often hold back traditional equipment-dependent networks, while also reducing CAPEX and OPEX. For these reasons, further network virtualization may take place not only in data centers, but also in WANs that need better bandwidth utilization and cost structures.