OFC 2022 was held in San Diego, California with a large number of active participants at the show, filling the exhibit halls after two years of mostly virtual attendance. However, to accommodate those unable to attend in person, OFC held many virtual sessions. I was one of those remotely attending. Even though I attended OFC virtually, I think my experience, while different than attending in person, was really good. That is, I learned a lot. Here are four of the things I learned and found the most interesting at OFC 2022.
The top of my list was the announcement by EFFECT Photonics that the company was buying the coherent DSP and FEC technology from Viasat. This combination brings together the most valuable components in any coherent transponder: InP-based photonic integrated circuit that includes a high-performance tunable laser, modulator, amplifier, and receiver all on one chip along with the high-speed digital electronics. The only items that EFFECT Photonics will need to source are the TIA and Driver when producing coherent pluggable optics in the future. To put this in perspective, one of the key attributes for both Acacia’s and Inphi’s value was having all of these technologies in-house.
The second thing I learned during OFC was the volume of coherent DSPs shipped by Cisco (Acacia), but maybe more importantly, how fast the ramp of shipments is occurring for the company’s newest coherent DSP (Greylock) that are used for 400 Gbps pluggable optics. During OFC, Cisco announced that cumulative shipments of the company’s 600 Gbps-capable DSP (Pico) by port volume was 100k, which converts to 50k DSP chips since each DSP supports two ports. The Pico DSP is primarily used for metro and long haul spans that require the best-performing optics. Cisco, also, announced that the cumulative shipments of Greylock was at 50k with nearly half shipped in the most recent fiscal quarter and with most being sold in a 400ZR QSFP-DD; The remainder is used in 400 Gbps CFP2-DCO. This is a very fast ramp for Greylock, considering it was introduced over a year after Pico.
The third item of focus at OFC this year seemed to center around what comes after 400ZR. While there was talk about the progress of 400ZR and the possibility of 800ZR in a few years, I felt the discussions were more about 400ZR+. It seems 400ZR+ will continue to be a marketing term and not a standard. That is to say, companies were announcing better-performing 400ZR+ compared to competitors. And as you know, better performance, product differentiation usually translates to non-standard. However, one thing in common is that the vendors are producing 400ZR+ in a QSFP-DD plug. I had originally thought that 400ZR+ would generally be used in a CFP2 package due to thermal requirements, but many of these companies have solved that problem and can deliver better-performing 400 Gbps with just an extra watt or two of power. Of course, this makes me wonder (out loud), would operators be willing to forgo the standards-based 400ZR with a 120 km limit for a non-standard based 400ZR+ with span limits that could exceed 600 km if it is also a QSFP-DD and consumes only a couple watts more? I think we all know the direction Windstream chose with the partnership with II-VI (400 ZR+ in QSFP-DD to enable the use of a ROADM line system).
The last item I want to mention is the excellent tutorials and classes that OFC holds every year where people volunteer their time to share what they do and to present informational sessions. I wasn’t able to watch all of the sessions that OFC recorded and made available to virtual participants, but the ones I watched were all done well and the presenters did an excellent job. One, in particular, that stood out for me was a session by Alexander Nikolaidis of Meta (Facebook) called Building a Global Content Provider Network at Scale. He gave a really good overview and understanding of how the company thinks through building and scaling a large content delivery backbone. He walked the audience through the choices and trade-offs that are considered. Interestingly, many of these choices and trade-offs are similar to those made by the largest telecom operators. So, at the end of the day, the challenges and choices for scaling a large backbone network aren’t that different whether it’s a large Internet content provider or a tier-one communication service provider.
