SDN + NFV: Do the enterprise benefits add up?

While network carriers have been driving the adoption of virtualized network functions for such things as load balancers and firewalls, networking vendors have been trying to ramp up sales of virtualized networking products by climbing on the bandwagon, declaring that you can execute virtualized network functions better with software-defined networks.

So what does this all mean for your enterprise? Before you can answer that question, you need to understand the attributes of the underlying technologies, network function virtualization (NFV) and software-defined networking (SDN), and the benefits each can bring to your network infrastructure.

The place to start is with a few basic definitions. NFV replaces expensive dedicated hardware appliances—either individual appliances or a few at a time—with generic servers that use software to provide a bunch of different virtualized network functions (VNFs) or services. SDN makes networks programmable so that operators can support applications using finite network resources.

2016 State of DevOps Report

SDN + NFV: Virtually better together

SDN makes networks programmable so operators can support applications using finite network resources. But moving to SDN means replacing hundreds to thousands of pieces of hardware throughout the network with generic servers; that’s a big undertaking, says John Fruehe, senior analyst at Moor Insights and Strategy. NFV replaces expensive dedicated hardware appliances—either individual appliances or a few at a time—with generic servers that use software to provide a bunch of different VNFs or services.

NFV enables operators, carriers, ISPs, and other enterprises to quickly deploy new applications for customers by provisioning supporting services quickly compared with the three-to-six-month provisioning time for services, i.e., functions provided inside proprietary appliances. This enables these service providers to go to market faster, beating the competition, according to Fruehe. Vendors, however, want to sell SDN, which they created to make the network programmable so network engineers can use a single portal to massage network characteristics such as traffic flow and bandwidth to best meet the needs of applications using finite network resources.

“When it’s vendor-driven like this, the adoption rate is slower,” says Fruehe. That’s why NFV is currently growing faster than SDN. Operators' desire for virtualized network functions or services and vendors' desire to sell SDN are driving this market. As a result, the SDN and NFV market should rise by 54 percent by 2020, according to "The SDN, NFV & Network Virtualization Ecosystem: 2015 - 2030 - Opportunities, Challenges, Strategies & Forecasts" from SNS Research via Research and Markets.

SDN controller vendors that are not startups will also offer NFV products in order to sell both, says Jennifer Pigg Clark, vice president of network infrastructure research at 451 Research. Specific vendor examples include Cisco, Ericsson, HPE, Juniper, and Nokia. They will sell them in tandem by pointing out how the SDN controllers support NFV by making it easier to provision and making it possible to do service chains flexibly. “With SDN, it is a lot easier for people to spin up VNFs where they are needed,” says Pigg Clark.

Selling the two virtualization technologies together makes it easier for vendors to explain them to customers. “If the vendors can put it all in one bucket, they can make it easier for customers to think about how they consume it,” says Fruehe.

How SDN and NFV work

Understanding how SDN and NFV work helps users better implement these complementary technologies in a network.

An SDN determines expedient paths through the network and delivers data traffic to its destination, according to Pigg Clark. A SDN centralizes network control in software, freeing it from proprietary hardware appliances.

An SDN also programs and optimizes the network, increasing the availability of finite network resources, such as bandwidth, to stretch the network as far as possible to support the needs of applications dynamically, according to Marc Cohn, vice president of network strategy at the Linux Foundation.

The Linux Foundation started the Open Orchestrator (OPEN-O) project for orchestrating or stringing together VNFs with open-source software, according to Cohn. Implementing VNFs will initially benefit the operators. Examples of such functions include firewalls, which secure the network; packet inspection, which examines data in transit at a fine-grained level, typically for security; and load balancers, which ensure that the network shares workloads evenly. These traditionally appear as proprietary appliances at the network edge. With NFV, they will live together in generic servers at the edge of the network.

NFV turns common network functions into virtualized network functions. This might include deploying services such as firewalls in VNFs or moving software-centric services inside commercial, off-the-shelf servers. NFV enables service chaining. This allows the set of services necessary to support a new application for a customer to be provisioned and deployed more quickly and easily. Service chaining also allows a user to scale up a service without the need for any additional hardware to support it. Enterprises provision different services inside these service chains based on the application they serve, connecting those services across the network edge. An email application, for example, could require a service chain of varying virus, malware, and antispam services; a VoIP application could add a traffic-shaping service to the mix, while removing other services, such as antispam services.

NFV allows service providers to offer pricing based on software licenses and usage, like a utility or the cloud, according to John Isch, director of network and voice center of excellence at Orange Business Services in the Americas. This pricing model is more precise, focuses on the software, and enables the customer to pay less by paying only for the services they use.

Instead of using specific hardware that can only do certain things with a single, fixed function and having to add more appliances as more services are needed, an IT professional can buy any server hardware that does the job, load several different services on the same server, and get it on the network quickly. This hardware lives at the edge of the network between the telecom or the enterprise and its customer.

SDN replaces traditional routers and switches, enabling the enterprise customer to directly interact with those services. It allows the customer to purchase and implement new functions through a single portal, according to Pigg Clark. SDN lives in many devices throughout the core network. Both SDN and NFV are technologies that can work without the other because they perform two separate tasks; however, they complement each other.

SDN, NFV, and 5G

It’s important to differentiate SDN and NFV from 5G. Whereas technologies such as 5G can provide an underlying network and the final connection between the enterprise and the customer, SDN and NFV make the best use of that underlying network by optimizing, securing, and providing other services to that network and the applications it serves. “It would be crazy to deploy 5G without NFV, because 5G is about flexibility, just like NFV,” says Dimitris Mavrakis, principal analyst for intelligent networks at Ovum.

Benefits for the enterprise

Before NFV and the cloud, these network functions or services were supplied in dedicated appliances that took up to six months to provision, according to Moor Insights & Strategy's Fruehe.

With NFV and the cloud, the process takes 30 minutes. Now, when any enterprise wants to offer a new service to a customer, it can start offering it immediately, beating the competition to market because it doesn’t have to wait six months for the network services that must accompany that service, says Fruehe.

Large multinational enterprises can benefit from using SDN to move traffic around their networks, says Mavrakis. “There are efficiencies when a fiber link goes down, because SDN will automatically reroute traffic through another path,” he explains.

SDN also benefits security. SDN’s distributed nature enables you to roll security closer to the devices where the data lives, says Fruehe. This removes some overhead for security, reducing that trade-off between trying to keep the network secure and delivering the right quality of service. Because SDN is more flexible, Fruehe adds, it enables a company to be responsive to security threats in a more immediate manner. A user can better shut down or dynamically reroute traffic flows, for example, if there is a problem.

By using virtualized services on generic off-the-shelf servers, enterprises can deploy these services right away, at a lower cost. SDN and NFV complete the virtualization trio, adding virtualized networks and services with existing virtualized servers, creating a fully virtualized environment that is much easier to manage, according to the Linux Foundation's Cohn.

Networking professionals and infrastructure architects benefit

SDN and NFV give information technology professionals better control of network performance, cost, and security parameters. The centralized, software-based nature of these technologies allows them to more closely align these parameters with the needs of the application, says Shawn Hakl, vice president of networking and managed services at Verizon. “They can very closely steer the application experience for the customer, ensuring the business value for them, while reducing costs for hardware and by using an on-demand, software-based model. They can also give the business agility and save on operational costs,” explains Hakl.

SDN and NFV affect IT professionals' careers as those individuals involved in bringing networking and services together become more aware of the need to move into these software disciplines versus hardware-focused disciplines, according to Cohn. “The Open Network Foundation instituted a certification program based on the demands there, to increase their value and their skill set to address the SDN world,” says Cohn. A couple of examples of new SDN skills include managing centralized SDN network controllers and using OpenFlow, the open-source programmable network protocol for SDN.

For networking and infrastructure professionals working in the trenches, SDN and NFV eventually simplify network management, although they initially make it more complex during the transition phase. “You have parallel networks because you have the old technology still running while you have the new technology up. It’s challenging to manage both at the same time,” says Pigg Clark.

Meshing the underlying network and the cloud

SDN and NFV act on and use the underlying network technology. This can be 4G, the coming 5G, a multiprotocol label switching (MPLS) network, or the Internet. The quality and integrity of the chosen underlying network on which to layer these virtualization technologies is key because, if network performance is degraded, SDN can only improve on that performance so much, says Orange Business Services' Isch.

SDN and NFV enable the business to separate out applications and use the best network connectivity option available for each based on cost and performance needs to support the customer experience, says Verizon's Hakl.

“The cloud is important because SDN and NFV leverage it for optimal performance, to create effective SDN and NFV infrastructure,” says Pigg Clark.

The way Orange uses SDN and NFV together in France is one good example of how these two technologies can mesh together now. “We have servers in our point-of-presence (POP) locations that give customers the ability to use a web page to define what VNFs they deploy on their connections, which come into those POPs,” says Isch.

If the customer wants to create a connection to the Internet, for example, then it would go into that web page, order a firewall, and the server applies the firewall as a VNF, says Isch. “The server connects the customer to the firewall and then enables whatever services or traffic the firewall definitions allow,” explains Isch.

SDN and NFV solutions and their value

There will be SDN and NFV solutions that are not vendor-centric, including VNFs from multiple vendors and vendor-agnostic devices on the customer premises, says Pigg Clark.

“Some SDN and NFV solutions will be vendor-agnostic, such as universal customer premise equipment. Those are still in their infancy but could be more prominent in the next year,” says Hakl.

The value for any enterprise is the same as it is for telecoms and ISPs: NFV solves a problem for organizations, and SDN helps.

“When a customer wants to deploy a new application to take advantage of a new revenue stream, it takes 30 minutes to create a virtual server to support it. Then, it takes three to six months to provision all the network and security services that must go with it in separate proprietary hardware appliances. By the time they do that, the opportunity they had is gone,” says Fruehe.

By setting up virtualized network and security services on generic servers instead of using proprietary appliances, you can have everything up at about the same time and take advantage of that opportunity ahead of your competition, says Fruehe. This agility also creates savings for those deploying the technologies in tandem. 

“The kind of service agility these technologies offer is the ability to launch and decommission services more rapidly and efficiently than is currently possible,” says Pigg Clark. Once an enterprise quickly makes a service available, a customer can turn it on or off much like a utility.

The combined cost savings of SDN and NFV could include labor savings in the short run and operational simplification in the long run, says Hakl.

This is important because it solves three overarching challenges for carriers: the need to carry more traffic, the need to do so with stagnant revenue growth limiting capital expenditure budgets, and the need to accelerate innovation and flexibility in the face of increasing OTT competition, says Pigg Clark.

SDN and 5G

In addition to savings and simplification, SDN supports an important communications technology, 5G. “SDN is at the core of 5G," says Hakl. "The use of SDN and NFV with 5G enables greater application responsiveness and better network programmability. You deploy a large number of devices using 5G and use the instrumentation from those devices to understand what is happening with the infrastructure. Then, you can use the programmable nature of the infrastructure to improve application performance."

Watch, determine, and act

SDN and NFV will ultimately appear together in production environments as telecoms, ISPs, and enterprises can get what they want from NFV and also get additional benefits from using SDN in support of those virtualized services. Enterprises and the information technology professionals they employ should consider SDN and NFV and decide where they might deploy these technologies to reap the most benefit. Finally, IT professionals should start learning SDN and NFV skills as soon as possible so they can stay relevant and employable in the market, which is increasingly moving to virtualization.

2016 State of DevOps Report
Topics: IT Ops