Your editors attended the 2017 Optical Fibers Communications (OFC) Conference for two days. Such a short visit is hardly sufficient to present a complete overview of what is considered the major annual worldwide event dealing with optical fiber communications. Yet, our brief glimpse of the exhibits and the papers presented should give the reader a feel for some of the major recent developments.
To begin with, the attendance of nearly 15,000 people from all over the world was a record high for the last few years, indicating that growth is on a upward trend.
We found the conference well organized and we were kept informed daily via email of the major presentations and exhibits taking place. The supporting staff was gracious and helpful, which greatly facilitated access to presentations and exhibits.
The meeting’s keynote is, as always, the plenary session. In this session, Urs Hölzle, senior vice president of technical infrastructure and Google Fellow at Google, presented projections of needs for the near future:
Capacity increasing by a factor of 2 every year with costs going down by a factor of 2.
Continued need for software defined optical networks (SDN), as big users don’t want vendor dashboards.
Increase in undersea bandwidth; Google has 12 transoceanic cables now.
Outage restore times must be limited to minutes, not days or weeks, as they are now.
This was followed the next day with a press briefing by Rafik Ward of Finisar, the company that is famous for vertical cavity surface emitting lasers and pluggable modules. The briefing focused on the following observations:
100 Gb/s QSP28 modules are becoming big products.
There is surprisingly little commonality among data center product vendors.
Developments in the next few years will focus on 200 and 400 Gb/s hardware.
Another breakthrough of the conference was the laboratory results obtained by Subsea Communications using a circulating fiber ring that indicates a single fiber can carry 70.4 Tb/s over 7,600 km [Citation1].
Finally, in a couple of days, we had the opportunity to observe the following trends:
Coherent Communications at 400 Gbs is now here to stay and growing. Several transponder modules make this channel capacity possible with the use of silicon electronics and QAM modulations up to QAM16. Transmission was demonstrated with 400-Gb/s at 56-GBd PDM-16QAM [Citation2].
Power efficiency and increased channel capacity through space division multiplexing was accomplished in a mutimode fiber with 12 cores. A transmission experiment using a 12-core fiber over ~14,350 km achieved a data rate of 105.1 Tb/s by using just 800mW of total pump power for the 12 EDFAs [Citation3].
400 Gbs Ethernet: AT&T completed first phase of a multi-phase field trial initiative of 400 Gigabit Ethernet (400GbE) transmission. The initial trial saw the company use an SDN controller to create a 400GbE service between New York and Washington, DC, alongside live traffic.
SDN: The continued growth of SDNadded a new degree of flexibility to reconfigurable optical add-drop multiplexers (ROADM) as demonstrated by AT&T and Verizon. This improved ROADM named CDC (colorless, directionless, contentionless) ROADM is an optical switch that allows any wavelength coming into the switch to be automatically sent to any switch/router port via a simple software command.
Mega data centers: With the continued reduction of local data centers and their shifting to mega data centers, such as those run by Google and Amazon, the insatiable demands for increased length and capacity between the elements of these mega centers’ leverages from all the improvements mentioned above, and in particular 400GbE and SDN.
Finally, looking into the horizon one cannot ignore the significant improvements brought on by plasmonic technology, an enabler of plasmonic modulators with demonstrated bandwidth of 170 GHz and baud rates of 60 Gbd with PAM-4 [Citation4].
Final comments
The topic of transoceanic communications was introduced in a superb OFS short course presented by Neal Bergano of TE SubSea Communications. Clint Schow of UC Santa Barbara gave a comprehensive overview of data center fiber communications. And, all the short courses that we sampled were outstanding.
It may be a sign of maturity or of overload: major vendors at OFC had scheduled technical discussions in advance. This limited access to “interesting” engineers on the exhibit floor.
All in all, OFC 2017 surpassed its standards by providing an exciting and instructive conference with great hospitality.
References
- Cai, J.- X., Batshon, H. G., Mazurczyk, M. V., Sinkin, O. V., Wang, D. Paskov, M., Patterson, W., Davidson, C. R., Corbett, P., Wolter, G., Hammon, T., Bolshtyansky, M., Foursa D., and Pilipetskii, A. 2017. 70.4 Tb/s Capacity over 7,600 km in C+L Band Using Coded Modulation with Hybrid Constellation Shaping and Nonlinearity Compensation. Optical Fiber Communications OFC 2017 Conference, Los Angeles, CA, March 19–24.
- Emmerich, R., Elschner, R., Schmidt-Langhorst, C., van Elzakke, G., Hoffmann, J., Umbach, A., Schubert, C. 2017. Colorless C-Band WDM System Enabled by Coherent Reception of 56-GBd PDM-16QAM Using an High-Bandwidth ICR with TIAs. Optical Fiber Communications OFC 2017 Conference, Los Angeles, CA, March 19–24.
- Sun, Y., Sinkin, O. V., Turukhin, A. V., Bolshtyansky, M. A., Foursa, D. G., and Pilipetskii, A. N. 2017. SDM for Power Efficient Transmission. Optical Fiber Communications OFC 2017 Conference, Los Angeles, CA, March 19–24.
- Hoessbacher, C., Josten, A., Baeuerle, B., Fedoryshyn, Y., Hettrich, H., Salamin, Y., Heni, W., Haffner, C., Schmid, R., Elder, D. L., Hillerkuss, D., Möller, M., Dalton, L. R., and Leuthold, J. 2017. Broadband plasmonic modulator enabling single carrier operation beyond 100 Gbit/s. Optical Fiber Communications OFC 2017 Conference, Los Angeles, CA, March 19–24.