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AT&T, Ciena, Fujitsu Test Open ROADM

December 21, 2016

Multivendor optical carrier networks have long been a dream. Remember all the excitement about SONET mid-span meets so many years ago? That excitement persists even today, but now the focus is around leveraging open networking and software-defined architectures to enable true multivendor optical networks.

Two cases in point are the recent work between AT&T and Fujitsu, and Facebook’s (News - Alert) Voyager effort.

AT&T has been engaged in an Open ROADM interoperability field trial with Ciena and Fujitsu. ROADM (News - Alert) stands for reconfigurable optical add/drop multiplexers. Transponders and ROADMs from Ciena and Fujitsu connected two IP/MPLS routers on a 100gbps optical wavelength carrying live customer traffic in the Dallas area.

A Dec. 9 blog by AT&T’s Andre Fuetsch mentioned that the goals of these new ROADMs include open hardware specifications, which enable ROADM gear from different vendors to be used in single metro area deployments, and software control, which allows for better management and routing of each wavelength of laser light coming into each switch.

“Data traffic on our wireless network surged more than 150,000 percent between 2007 and 2015,” Fuetsch wrote. “ROADMs are one of the workhorses pulling that growing load. We need the efficiency, innovation, and cost-savings that come from open ROADM specs to continue delivering the network performance our customers expect.”

While this all sounds promising, an April 16 blog by Fiber Optic Consultants raises questions about how widespread AT&T’s Open ROADM is likely to be.

“There is no question that it has been important for AT&T to push such narratives in order to persuade investors that its financial position will eventually improve with these actions,” wrote Mark Lutkowitz of Fiber Optic Consultants. “Yet, when pressed on the validity of these plans becoming a reality to the extent as promised, as a provider with the least amount of adaptability internationally, given its size and its age, it seems that it is forced to continually acknowledge that the focus is on greenfield applications, which by definition, precludes a massive amount of change.

“There is not much evidence to suggest that AT&T has become in reality substantially less operationally driven based on the old Ma Bell model, which has always advocated keeping elements in the network indefinitely,” Lutkowitz added. “In contrast, again, it is Verizon (News - Alert), despite its conservative stance on OLS, which has been quite a bit more innovative.”

As for Facebook, it has come out with an open DWDM transport solution called Voyager that is shaking up the optical networking arena. The company says Voyager the industry’s first white box transponder and routing solution.

This 1RU packet optical transport box, which features 12x100gbps QSFP 28 clients and 4x200gbps 16QAM on the line side, is more than just an idea. Facebook has partnered with subsystem provider Acacia Communications, semiconductor outfit Broadcom, hardware provider Celestica, optical and photonic company Lumentum, and open source software company Snaproute to build the solution, and Equinix (News - Alert) and MTN have already successfully tested it.

But anybody can build a Voyager solution if they want to, since Facebook and the Telecom Infra Project (to which Facebook has contributed the Voyager blueprint) are sharing the specs.

That would seem to be a threat to existing optical solutions providers, but at least a few optical companies say they consider it an opportunity. ADVA (News - Alert) Optical Networking and Coriant have gotten behind the Facebook/TIP Voyager effort.

Coriant is extending its networking software to enable engineering support for Voyager, providing DWDM transmission capabilities, and routing and switching for Voyager, according to the Facebook blog. Meanwhile, ADVA plans to provide commercial support for Voyager. Niall Robinson, vice president of global business development at ADVA, explained that means it will work to provide customers that are interested in putting Voyager in their networks with network management software and support. ADVA has not announced plans to manufacture Voyager, he added, but the company will sell it.

Edited by Maurice Nagle