DENVER -- NFV & Carrier SDN -- Software-defined networking is the glue enabling network operators to consolidate the management of their IP and optical network layers and save both capex and opex in the process, Heavy Reading Senior Analyst Sterling Perrin said today.

Speaking at Light Reading's NFV & Carrier SDN event here this morning, Perrin said combined IP-optical management is one of two major trends in the optical space for the virtualization era. The other is the growing influence of open source, as operators look for ways to move forward faster and bring new services to market more quickly.

"These are two separate trends, but they overlap," he commented.

Figure 1: Pay No Attention to the Name Tag This is actually Sterling Perrin, doing his morning presentation.

For some time now, Ethernet switching and optical networking have been combined. There have been attempts to physically combine IP and optical for more than a decade, but those efforts have failed for lack of a business case, Perrin said. The lack of optical interoperability between different vendors' gear was another stumbling block.

What is gaining traction now is the notion of integrating the control and management of IP and optical layers with SDN and orchestration, without having to physically integrate IP routers and optical gear, he noted. In a recent Heavy Reading survey, 57% of operators identified IP and optical network integration as their top network optimization goal over the next three years.

"Network operators are seeing the big benefits they can get by doing that [integration], mostly around network optimization and network efficiency," Perrin said.

He pointed to early pre-SDN work by Telefónica and Deutsche Telekom AG (NYSE: DT) to examine their core networks and quantify ways to save a lot of capex by managing IP and Optical together, giving each layer awareness of what the other is doing. That broader awareness allows decisions to be made more rapidly – and ultimately in automated fashion -- to respond to network events such as congestion or equipment failure.

SDN control is at the core of today's solution, providing software control of underlying hardware, as the industry move away from purpose-built systems with integrated hardware and software, he says.

Google (Nasdaq: GOOG) used SDN to drive its wide area network utilization up to 95% levels, Perrin said -- that's unheard of in the telecom space, where network utilization is more typically in the 40% to 50% range.

"For telecom, by combining IP and optics with SDN, you can vastly increase utilization and that translates into major savings on ports and ultimately opex savings as well," he said.

Much of the latter comes from automating processes that once required a human touch -- something that also becomes essential because people can't physically reprogram networks fast enough to make the necessary decisions and changes, he adds.

And that's where open source becomes a major factor, enabling management and control of underlying networks, to meet the network operators' goals of delivering new services faster and enabling them to be more easily customized.

"Open source becomes the route to open standardization so you can mix the IP layer and optical layer across vendors," Perrin said.

Equipment vendors are under pressure to move away from converged systems to automated, modular, open systems, the analyst notes. Past efforts at bringing the IP and optical layers together required single-vendor deployments, which network operators don't want to do. But getting standards in place for interoperability has been time-consuming and tedious.

"Network operators are concerned about the pace at which they can get things done in standards bodies and we are seeing a rise in popularity of open sources groups as a result," he says, citing groups such as Open Platform for NFV Project Inc. , the Open Networking Foundation , OpenDaylight , ONOS and CORD.

Open source groups offer a faster path to interoperability -- measured in months not years -- as well as exposure to new ideas from participants outside of telecom, and reduced costs of development, since base codes are provided in the open source process, Perrin says. Open source also provides greater hardware and software modularity, which is becoming important to telecom because it enables increased flexibility and scalability.

Facebook 's work in launching the Telecom Infra Project (TIP) earlier this year and a number of very telecom-specific working groups in May, including an optical network group, are being well-received by many operators, he said. (See Facebook: TIP Will Open Telecom Hardware.)

"Operators have been lamenting their inability to move as fast as Facebook," he commented. "Now if you can start doing things their way, maybe you can move faster."

Traditional standards bodies may not disappear entirely, Perrin admitted -- they may become the place where open source organizations take their work for final standardization -- but the open source work is what is fueling the greatest activity today for the network operators moving the fastest to embrace SDN as critical to their transport networks.

— Carol Wilson, Editor-at-Large, Light Reading