The vendor's new XR Optics technology could cut carrier opex and capex in service providers' metro networks. But can the company get everyone else to buy into coherent optical sub-carrier aggregation?

Phil Harvey, Editor-in-Chief

September 30, 2019

7 Min Read
Infinera: Making Optical Interesting Again

The optical networking market finally is buzzing about something other than a merger or acquisition and Infinera's right in the middle of it.

Infinera announced last week it has developed a new technology it calls XR Optics, a coherent pluggable optical transceiver that can generate lots of independent optical signals with dedicated data streams that can be routed to different destinations. That's a mouthful, but chew slowly and enjoy.

Infinera founder David Welch said he saw a disconnect between the kinds of traffic flows happening in metro networks and the technology used to address them. Traffic patterns from hundreds of endpoints looked like a hub and spoke topology but optical networks are made up of a series of point-to-point connections.

Metro networks must move traffic from many, many endpoints back to a small number of hub locations, Internet peering points or data centers, so a lot of signal aggregation has to happen along the way, Welch explained in a conversation with Light Reading earlier this month.

For each access node in a traditional network -- a point to point topology -- you need a transceiver on either end of the optical signal. A 16-node system requires 32 transceivers. Welch said he and Infinera developed XR Optics to behave more like a radio at a cell tower -- where a single radio can talk to hundreds or thousands of endpoints -- and handle them individually.

If you had, for example, a single high-end 400G transceiver that could operate at a range of frequencies to communicate individually with lots of endpoints in remote locations, you wouldn't have to match each endpoint and network hub with the same optics: You could use smaller transceivers that were set up for the individual capacity needs of those remote endpoints.

If the technology works as described, a 16-node system would only need 17 transceivers, not 32.

XR Optics is part of the evolutionary path that Infinera's been on for quite a while, Welch said. A few years ago, Infinera introduced Nyquist capabilities, a method where a single transceiver can generate multiple independent optical transmissions (subcarriers). These Nyquist subcarriers use the same amount of optical spectrum that one carrier would use. The technique allowed Infinera to increase network capacity without sacrificing transmission distance. Nyquist subcarriers were part of the secret sauce that made Infinera's Infinite Capacity Engine (ICE4) technology such a hit.

The next breakthrough came when Infinera realized it could control each individual subcarrier generated by a single laser, said Robert Shore, Infinera's senior VP of marketing. This discovery led to Infinera's ICE6 technology, which is still in development. "ICE6 is a huge evolutionary leap in the use and control of subcarriers," Shore told Light Reading.

Light Reading covered the move from Infinera's ICE4 all the way to ICE6 -- and the shrinking development times between generations of optical networking technologies -- in this 2018 interview:

{videoembed|741578}



"With XR Optics we've taken another step forward because now we realized that not only can we individually control each subcarrier, but we can send them all to different destinations," Shore said.

When any device can talk directly to any other device in the metro, the point-to-point topology starts looking more hub-and-spoke.

"People put all these intermediate aggregation devices in their network that have the purpose of aggregating lower speed signals into higher speed signals so that they can hit that core right at the high-speed interface," Shore said. "If I can do that using this [XR] technology, I can do all the aggregation purely in the optical domain... I can combine all the traffic from all the subcarriers from lots of different locations and feed it onto a single fiber and feed that fiber into that 400G router port."

The takeaway: It would reduce the number of ports needed and eliminate the need for aggregation devices. That would lower capex for telco or cable service providers or enterprise customers. "In addition, router capex, power consumption and footprint are optimized, resulting in further savings in capex and opex," writes Dave Kang, an analyst at B. Riley FBR Research, in a note to clients last week. "XR could be an ideal solution for 5G front-haul and mid-haul, CATV, PON and high-speed enterprises."

This could compete with 400G ZR pluggables -- another kind of coherent optical transceiver that is going to plug right into routers. However, 400G ZR is both a point-to-point technology and is used mainly in DCI (data center interconnect) applications, said Sterling Perrin, principal analyst at Heavy Reading.

"[Infinera is] taking pluggables technology and they're coming up with a way that it can be multi-point technology, which is the way that better suits telecom operator networks," Perrin told Light Reading. "If this takes off, they're really opening up an opportunity for pluggables in a way that doesn't exist right now."

Other options for metro networking abound and other suppliers will weigh in as Infinera gets closer to making XR a reality. Infinera's main obstacle will be the service provider status quo -- it's just easier not to change network topology to embrace new tech, Perrin said. But there's a lot of momentum around pluggables and the IP-over-DWDM architecture, he said. And, he added, software-defined control is very important and this development would require service providers to really understand how they control traffic flows "because metro networks are really complex." Perrin added: "This is not an easy decision for operators at all."

Working in Infinera's favor, though, was the company's choice to not go it alone. This new technology won't be housed in a box that only Infinera would or could build. Infinera will work with an ecosystem of other companies; router vendor Arista and optical components manufacturer Lumentum were quoted in the press release announcing XR Optics.

"We have not announced any official relationship with Arista or Lumentum," Infinera's Shore told Light Reading via email. "We have been discussing XR Optics with a wide range of network operators as well as system and component suppliers… We plan to work with the industry to ensure we create the multisource supply chain at the module level and are working on agreements to that end."

The next step in the process is for Infinera to forge and announce official partnerships to support its technology. The company has already demonstrated the tech and talked it up at several panels during the recent ECOC (European Conference on Optical Communications) in Dublin.

Depending on the partnerships announced, Infinera will either turn heads or open wallets -- or maybe a little of both. "This surprising partnership between ANET [Arista] and INFN [Infinera] once again accentuates our belief that INFN's highly-differentiated technology could drum up interest among larger comm equipment vendors such as ANET or Juniper to eventually acquire the company, which would be much cheaper compared to Cisco's offer of $2.6B for ACIA [Acacia]," Kang wrote on Sept. 24.

Indeed, Infinera's attractiveness as a differentiated technology supplier is a bit more interesting than its status as yet another vendor Ciena is outrunning in just about every optical transport market. The company's timing is key here.

"The 400 ZR stuff is going to ship next year and we know a lot of companies deploying 5G are evaluating their X-haul transport architectures right now," Perrin said. "We know 2020 and 2021 are going to be big, big years for, if not building, at least deciding what that architecture is. The same thing is true with cable companies and fiber deep. So [Infinera] needs to get in there as soon as they can with a serious option."

Okay, so maybe the conversation did bend itself back around to mergers and acquisitions. But the buzz of new technology in this space is exciting and nearly every major service provider will have a stake in what happens next.

Related posts:

Phil Harvey, US Bureau Chief, Light Reading

About the Author(s)

Phil Harvey

Editor-in-Chief, Light Reading

Phil Harvey has been a Light Reading writer and editor for more than 18 years combined. He began his second tour as the site's chief editor in April 2020.

His interest in speed and scale means he often covers optical networking and the foundational technologies powering the modern Internet.

Harvey covered networking, Internet infrastructure and dot-com mania in the late 90s for Silicon Valley magazines like UPSIDE and Red Herring before joining Light Reading (for the first time) in late 2000.

After moving to the Republic of Texas, Harvey spent eight years as a contributing tech writer for D CEO magazine, producing columns about tech advances in everything from supercomputing to cellphone recycling.

Harvey is an avid photographer and camera collector – if you accept that compulsive shopping and "collecting" are the same.

Subscribe and receive the latest news from the industry.
Join 62,000+ members. Yes it's completely free.

You May Also Like