NFV plus SDN: The whole is greater than the sum of its parts

PALO ALTO, Calif.--Technically speaking, network functions virtualization (NFV) and software-defined networking (SDN) do not need to be deployed together. Yet many vendors attending the Carrier Network Virtualization event, sponsored by Informa Telecoms & Media, contend carrier-grade NFV actually does need SDN to come to full fruition.

Informa Carrier Network Virtualization

Attendees on the exhibit floor at Informa's Carrier Network Virtualization event. (Source: Informa Telecoms & Media)

There is a huge amount of overlap across SDN, which separates the control and forwarding planes, and NFV, which aims to replace proprietary hardware with industry-standard equipment. And while NFV and SDN do not depend upon one another, it is becoming clearer that NFV will benefit from companion SDN deployments.

"True NFV, large scale, will require SDN," Cam Cullen, vice president of global marketing for networking company Procera Networks, told FierceWirelessTech. In the absence of SDN, lots of extra scripting and orchestration is needed, he noted.

According to Guy Machlev, director of cloud solutions for Alcatel-Lucent, SDN has the necessary strengths for responding to the frequent changes needed by NFV. That is because SDN is instantaneous and automatic. It is also policy driven, rather than relying upon manual design or scripting, and is independent of hardware choices.

Anshu Agarwal, vice president of marketing at SDN provider ConteXtream, told FierceWirelessTech that operators need SDN to make NFV scale. "Your functions would be hanging by themselves," without SDN, she said. "The promise of NFV can only be realized by SDN."

ConteXtream's most recent production deployment was with the largest U.S. MSO, which has about 50 million subscribers, pointing to Comcast. In May, ConteXtream announced that a Tier 1 U.S. wireless operator—likely Verizon Wireless (NYSE:VZ)--had deployed its SDN technology to virtualize almost half of its network.

Supporters of NFV say it opens up hardware choices for operators, enabling them to exit the world of single-vendor legacy solutions. In cases where operators must continue to rely upon legacy equipment, they should pursue network abstraction by aggregating the different elements on a middle level where they can be accessed and managed via a programmable interface, said Ulf Avrin, CEO of PacketFront Software.

Edward Schneider, managing director at Quan Funds, took a dig at operators that he said are slowing the pace of innovation by remaining too dependent upon proprietary Cisco hardware and software in the data center. Until operators "have the courage to break away from Cisco" and fully embrace open source solutions, there will be data center bottlenecks, he said.

Another theme of the conference was the need for telcos to get beyond the traditional five 9s of reliability and instead follow the Silicon Valley mindset by building networks that accept and tolerate failure because they can reroute services on the fly.

"This is the greatest shift since the invention of IP itself," he said. "We must identify habits from the past to carry forward, invent new practices for the future and ruthlessly differentiate between the two," said Matt Beal, CTO at CenturyLink.

Similarly, Rick Pierson, innovation and strategy executive from JT Global, said SDN and NFV will be disruptive only from the perspective that they will disrupt businesses if internal processes do not change as well. He said the radio access network (RAN) will be the last network component to be virtualized but asked where the business model is to justify that.

"I'm very concerned" that the focus of SDN and NFV has been on cost savings rather than the development of new business models and revenue streams, he said.

Related articles:
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Informa: SDN, virtualization will first be applied to network core
ONF counts 100 members backing its SDN advocacy effort
Survey: U.S. mobile operators helping drive SDN adoption
ConteXtream's whodunit: Which Tier 1 carrier launched massive SDN deployment?