Reflections on OFC 2017

Mood, technologies, notable announcements - just what are the metrics to judge the OFC 2017 show held in Los Angeles last week?

It was the first show I had attended in several years and the most obvious changes were how natural the presence of the internet content providers now is alongside the telecom operators, as well as systems vendors exhibiting at the show. Chip companies, while also present, were fewer than before.

Source: OSA

Another impression were the latest buzz terms: 5G, the Internet of Things and virtual reality-augmented reality. Certain of these technologies are more concrete than others, but their repeated mention suggests a consensus that the topics are real enough to impact optical components and networking.

It could be argued that OFC 2017 was the year when 400 Gigabit Ethernet became a reality 

The importance of 5G needs no explanation while the more diffuse IoT is expected to drive networking with the huge amounts of data it will generate. But what are people seeing about virtual reality-augmented reality that merits inclusion alongside 5G and IoT?  

Another change is the spread of data rates. No longer does one rate represent the theme of an OFC such as 40 Gigabits or 100 Gigabits. It could be argued that OFC 2017 was the year when 400 Gigabit Ethernet became a reality but there is now a mix of relevant rates such as 25, 50, 200 and 600 gigabits.    

Highlights

There were several highlights at the show. One was listening to Jiajin Gao, deputy general manager at China Mobile Technology, open the OIDA Executive Forum event by discussing the changes taking place in the operator's network. Gao started by outlining the history of China Mobile's network before detailing the huge growth in ports at different points in the network over the last two years. He then outlined China Mobile's ambitious rollout of new technologies this year and next.

China's main three operators have 4G and FTTx subscriber numbers that dwarf the rest of the world. Will 2017 eventually be seen as the year when the Chinese operators first became leaders in telecom networking and technologies?

The Executive Forum concluded with an interesting fireside discussion about whether the current optical market growth is sustainable. The consensus among representatives from Huawei, Hisense, Oclaro and Macom was that it is; that the market is more varied and stable this time compared to the boom and bust of 1999-2001. As Macom’s Preetinder Virk put it: "The future has nothing to do with the past". Meanwhile, Huawei’s Jeffrey Gao still expects strong demand in China for 100 gigabits in 2017 even if growth is less strong than in 2016. He also expects the second quarter this year to pick up compared to a relatively weak first quarter.

OFC 2017 also made the news with an announcement that signals industry change: Ciena's decision to share its WaveLogic Ai coherent DSP technology with optical module vendors Lumentum, Oclaro and NeoPhotonics.

The announcement can be viewed several ways. One is that the initiative is a response to the success of Acacia as a supplier of coherent modules and coherent DSP technology. System vendors designed their own coherent DSP-ASICs to differentiate their optical networking gear. This still holds true but the deal reflects how the progress of merchant line-side optics from the likes of Acacia is progressing and squeezing the scope for differentiation.

The deal is also a smart strategic move by Ciena which, through its optical module partners, will address new markets and generate revenues as its partners start to sell modules using the WaveLogic Ai. The deal also has a first-mover advantage. Other systems vendors may now decide to offer their coherent DSPs to the marketplace but Ciena has partnerships with three leading optical module makers and is working with them on future DSP developments for pluggable modules.

The deal also raises wider questions as to the role of differentiated hardware and whether it is subtly changing in the era of network function virtualisation, or whether it is a reflection of the way companies are now collaborating with each other in open hardware developments like the Telecom Infra Project and the Open ROADM MSA.

Another prominent issue at the show is the debate as to whether there is room for 200 Gigabit Ethernet modules or whether the industry is best served by going straight from 100 to 400 Gigabit Ethernet.

Facebook and Microsoft say they will go straight to 400 gigabits. Cisco agrees, arguing that developing an interim 200 Gigabit Ethernet interface does not justify the investment. In contrast, Finisar argues that 200 Gigabit Ethernet has a compelling cost-per-bit performance and that it will supply customers that want it.  Google supported 200 gigabits at last year’s OFC.   

Silicon photonics

Silicon photonics was one topic of interest at the show and in particular how the technology continues to evolve. Based on the evidence at OFC, silicon photonics continues to progress but there were no significant developments since our book (co-written with Daryl Inniss) on silicon photonics was published late last year.

One of the pleasures of OFC is being briefed by key companies in rapid succession. Intel demonstrated at its booth its silicon photonics products including its CWDM4 module which will be generally available by mid-year. Intel also demonstrated a 10km 4WDM module. The 4WDM MSA, created last year, is developing a 10km reach variant based on the CWDM4, as well as 20km and 40km based designs.

Meanwhile, Ranovus announced its 200-gigabit CFP2 module based on its quantum dot laser and silicon photonics ring resonator technologies with a reach approaching 100km. The 200 gigabit is achieved using 28Gbaud optics and PAM-4.

Elenion Technologies made several announcements including the availability of its monolithically integrated coherent modulator receiver after detailing it was already supplying a 200 gigabit CFP2-ACO to Coriant. The company was also demonstrating on-board optics and, working with Cavium, announced a reference architecture to link network interface cards and switching ICs in the data centre. 

I visited Elenion Technologies in a hotel suite adjacent to the conference centre. One of the rooms had enough test equipment and boards to resemble a lab; a lab with a breathtaking view of the hills around Los Angeles. As I arrived, one company was leaving and as I left another well-known company was arriving. Elenion was using the suite to demonstrate its technologies with meetings continuing long after the exhibition hall had closed.

Two other silicon photonics start-ups at the show were Ayar Labs and Rockley Photonics.

Ayar Labs in developing a silicon photonics chip based on a "zero touch" CMOS process that will sit right next to complex ASICs and interface to network interface cards. The first chip will support 3.2 terabits of capacity. The advantage of the CMOS-based silicon photonics design is the ability to operate at high temperatures. 

Ayar Labs is using the technology to address the high-bandwidth, low-latency needs of the high-performance computing market, with the company expecting the technology to eventually be adopted in large-scale data centres.

Rockley Photonics shared more details as to what it is doing as well as its business model but it is still to unveil its first products.

The company has developed silicon photonics technology that will co-package optics alongside ASIC chips. The result will be packaged devices with fibre-based input-output offering terabit data rates.

Rockley also talked about licensing the technology for a range of applications involving complex ICs including coherent designs, not just for switching architectures in the data centre that it has discussed up till now. Rockley says its first product will be sampling in the coming months. 

Looking ahead

On the plane back from OFC I was reading The Undoing Project by Michael Lewis about the psychologists Danny Kahneman and Amos Tversky and their insights into human thinking.

The book describes the tendency of people to take observed facts, neglecting the many facts that are missed or could not be seen, and make them fit a confident-sounding story. Or, as the late Amos Tversky put it: "All too often, we find ourselves unable to predict what will happen; yet after the fact, we explain what did happen with a great deal of confidence. This 'ability' to explain that which we cannot predict, even in the absence of any additional information, represents an important, though subtle, flaw in our reasoning." 

So, what to expect at OFC 2018? More of the same and perhaps a bombshell or two. Or to put it another way, greater unpredictability based on the impression at OFC 2017 of an industry experiencing an increasing pace of change.