400G - GIGALIGHT

25Mar, 2024

GIGALIGHT Innovatively Launches Linear 400G DR4 CPO Silicon Optical Engine

Shenzhen, China, March. 25, 2024 – GIGALIGHT recently announced the launch of a 400G DR4 CPO silicon optical engine based on linear direct drive technology. This is a subset of Gigabyte’s innovative products for the next optical network era:

1.The linear silicon optical engine 400G DR4 CPO is composed of SOCKET slot packaging and LPO linear direct drive technology. Compared with the traditionally defined NPO/CPO, linear CPO silicon photonic engines remove DSP, which can significantly reduce system-level power consumption and costs. The light emitted from the TX end of this engine is in the range of 0-3dBm, and the extinction ratio falls in the range of 4-5dB. TDECQ<2.5dB, generally falls within 1-2dB. Wavelength is 1304.5nm-1317.5nm; SMSR≥30dB; RX end OMA sensitivity <-5.5dBm. The eye diagram is as follows:

2.Through the test board with DSP and external pluggable light source specially developed by GIGALIGHT, the linear 400G CPO optical engine can be completely restored.

3.GIGALIGHT plans to upgrade the engine to 800G and 1.6T through higher-density advanced packaging technology.

GIGALIGHT’s research on CPO originated from the Shenzhen Science and Technology Innovation Commission’s co-packaging CPO optical project undertaken by the company. Linear CPO is a relatively friendly technology form that can implement higher-speed and higher-density switches under the premise of limited low-nanometer manufacturing processes. Reduce power consumption and improve system interconnection reliability. Truly realize the goal of de-DSP for next-generation switches. Compared with the pluggable LPO technology that has fundamental flaws that the industry is currently working on, linear CPO is a stable technology. It should be said objectively that linear CPO is technically inspired by LPO and original CPO technology, mainly to more easily solve many problems such as system signal consistency and reliability. GIGALIGHT will delve into silicon optical linear CPO technology solutions.

About GIGALIGHT

As an open optical networking explorer, Gigalight integrates the design, manufacturing, and sales of both active and passive optical devices and subsystems. The company’s product portfolio includes optical modules, silicon photonics modules, liquid-cooled modules, passive optical components, active optical cables, direct attach copper cables, coherent optical communication modules, and OPEN DCI BOX subsystems. Gigalight focuses on serving applications such as data centers, 5G transport networks, metropolitan WDM transmission, ultra-HD broadcast and video, and more. It stands as an innovative designer of high-speed optical interconnect hardware solutions.

13Mar, 2024

GIGALIGHT 400G QSFP-DD SR4, Exclusive Design To Help Data Center Interconnection

Moving towards the supercomputing era, data centers have ushered in rapid development. With the continuous evolution of technology, the rise of AI supercomputing is leading the wave of innovation in the digital field. In this era with data as the core, the demand for data centers is not only the expansion of scale, but also the urgent desire for high-speed transmission. The transmission rate of 400G/800G, just like a powerful digital trend, is redefining data centers infrastructure.

In this article, Gigalight introduces you to a brand new 400G product: 400G QSFP-DD SR4 optical module, and see how it is used in today’s data centers.

Existing 400G network solutions

The high-speed network in the GPU cluster mainly consists of high-speed network cards, optical connectors (optical transceivers and cables) and high-speed switches. Currently, servers equipped with H800GPU mainly use NVIDIA CX7 400G network cards, and there are many choices of switches on the market. These options include 64400G QDD switches based on BCM 25.6T Tomahawk4 (TH4) chips, 64800G switches based on BCM 51.2T chips, switches based on Cisco Nexus chips, and 400G/800G switches based on NVIDIA Spectrum chips. From a market perspective, 400G QDD switches are currently the dominant choice. The following figure shows the commonly used network architecture of clusters:

It can be observed that the mainstream 400G switches in the market use 56G SerDes, while the CX7 network card uses 112G SerDes. In order to keep the network connected, this difference needs to be considered when selecting optical transceivers to ensure component compatibility and proper operation. As shown in the picture:

In order to solve this problem, everyone currently chooses 400G QSFP-DD DR4 optical modules on the switch side, and uses 400G OSFP DR4 optical modules on the server side. The connection is shown below:

This is a good solution within a connection distance of less than 500m, but if the connection distance does not exceed 100m, choosing the DR4 solution is a bit wasteful. Therefore, the short-distance 400G QSFP-DD SR4 using low-cost 850nm VSCEL laser is a good choice. It is much cheaper than DR4 and can meet the transmission distance requirement of 100m.

400G QSFP-DD SR4 is inserted into the 400G QSFP-DD 8×50G PAM4 port, which can be interconnected with the 400G OSFP (4×100G PAM4) network card, and the interconnection between 400G QSFP-DD SR4 and 400G OSFP SR4 can be realized. . If shown:

Gigalight’s newly launched 400G QSFP-DD SR4 electrical port uses 8×50G PAM4 modulation, and the optical port uses 4×100G PAM4 modulation. Compared with 400G QSFP-DD SR8, it reduces 4 lasers and achieves lower Power consumption and price, power consumption is less than 8W. Using MPO12 optical port, it can meet 60m transmission with OM3 multi-mode fiber, and 100m transmission with OM4 multi-mode fiber.

The release of Gigalight’s 400G QSFP-DD SR4 fills the gap in short-distance 400G data center interconnection solutions and provides a more comprehensive choice for your data center.

9May, 2023

GIGALIGHT Launches 400G QSFP-DD/QSFP112 DR4++ SiPh Optical Modules, Unlocking Long-Distance Performance

Shenzhen, China, May 9, 2023 – To meet the increasing demand for high-speed transmission, low power consumption, and low insertion loss performance from data centers, communication operators, cloud computing service providers, and large enterprise users, GIGALIGHT today launched the 400G QSFP-DD/QSFP112 DR4++ 10km silicon photonics module, unlocking long-distance performance of silicon photonics.

As an open optical network device explorer, GIGALIGHT has already launched a variety of silicon-based integrated 100G and 400G optical modules for 500m to 10km transmission since the introduction of the 400G QSFP-DD DR4 500m SiPh optical module in 2021. Now, with mature silicon photonics integration technology, the power budget of the SiPh optical module can fully meet the 10km transmission requirements.

The GIGALIGHT 400G QSFP-DD/QSFP112 DR4++ 10km silicon photonics module has the following advantages:

400G QSFP-DD DR++

Compliant with QSFP-DD MSA, supports 8 channels of 50G-PAM4 electrical signals and 4 channels of 100G PAM4 optical signals, and supports dual-fiber transmission up to 10km. The module’s transmit end uses a highly integrated silicon photonics solution, and the receive end uses a PIN detector. OMA RXsen meets -7.1dBm @ 2.4E-4 Pre-FEC 26.5625GBd, and power consumption is less than 10W.

Next-generation 400G module: 400G QSFP112 DR++

Compliant with QSFP112 MSA, supports 4 channels of 112G-PAM4 electrical and optical signals, and supports dual-fiber transmission up to 10km. The module’s transmit end uses a highly integrated silicon photonics solution, and the receive end uses a PIN detector. OMA RXsen meets -7.1dBm @ 2.4E-4 Pre-FEC 53.125GBd, and power consumption is less than 10W.

About GIGALIGHT

As an open optical network device explorer, GIGALIGHT integrates the design, manufacturing, and sales of active and passive optical devices and subsystems. Its products mainly include optical modules, silicon photonics modules, liquid-cooled modules, passive optical components, active optical cables, direct attach copper cables, coherent optical communication modules, and OPEN DCI BOX subsystems. GIGALIGHT focuses on serving applications such as data centers, 5G transport networks, metropolitan wavelength division multiplexing (WDM) transmission, and ultra-high-definition broadcasting and video. It is an innovative high-speed optical interconnect hardware solutions provider.

30Dec, 2022

GIGALIGHT Mass-Produces 400G Silicon Photonics Transceivers to Ring of the 2023 New Year

Shenzhen, China, Dec 30, 2022 – Before the 2023 New Year’s bell rings, GIGALIGHT has announced the establishment of the mass production line of 400G silicon photonics transceivers and started the mass production journey. The current preset production capacity of the production line is an annual output of 150,000 high-speed silicon photonics transceivers, which can be expanded upwards to the production of key products such as 800G silicon photonics transceivers and CPO, and can provide OEM services for global customers.

Before the establishment of this production line, GIGALIGHT has completed the small batch shipment of silicon photonics transceivers of GEN1, and the GEN2 modules of the mass production line have the following characteristics:

Optimized APC (automatic power control) algorithm, the output power of the module at three temperatures is more than 0dBm
Accurate three-temperature silicon photonics bias control algorithm makes the module maintain excellent eye diagram and BER performance at three temperatures
A more accurate MZ modulator automatic locking algorithm ensures real-time and accurate locking under three-temperature conditions
High coupling efficiency and high reliability optical package
Low power consumption and low cost design

GIGALIGHT’s independent silicon photonics production line includes a light source design and packaging platform, a filpchip bond & wire bond packaging platform, a silicon photonics chip coupling glue process platform, and an automated debugging and testing system. These self-developed production and testing systems make the mass production of silicon photonics transceivers full of proprietary technologies, and a deep understanding of silicon photonics chips is also a special asset of GIGALIGHT.

GIGALIGHT’s silicon photonics industry started earlier, but the company experienced intermittent delays due to the impact of the US patent case. The GIGALIGHT R&D team finally completed the acceptance of the Shenzhen Science and Technology Innovation Commission’s silicon photonics project in 2021. The mass production currently underway is the crystallization of this multi-year achievement.

The development of silicon photonics has twists and turns, and the industry generally believes that it is an industry technology trend. Starting from 400G optical modules, silicon photonics can already form a very good complementary relationship with EML platform products. Although there is currently no obvious cost advantage, the development concept and technical identity advocated by silicon photonics technology still inspire the enthusiasm of chip manufacturers and many customers in the industry. The development of GIGALIGHT’s silicon photonics module has many intersections with the industry’s silicon photonics industry chain. It is based on open communication that inspires the driving force to move forward.

“A long time ago, we chose the silicon photonics industry, and now we must continue to do it until the dawn shines!” said Mr. Li, chairman of GIGALIGHT.

About GIGALIGHT

As the open optical network device explorer, GIGALIGHT integrates the design, manufacture and sales of active & passive optical devices and subsystems. The main products are optical transceivers, silicon photonics transceivers, liquid cooling transceivers, optical passive components, AOC & DAC, coherent optical modules and open DCI BOX subsystems. GIGALIGHT is a hardware solution provider of innovatively designed high-speed optical interconnection that focuses on data center, 5G carrier network, metro WDM transmission, UHD broadcast video and other application fields.

12Jul, 2022

GIGALIGHT Releases 400G Data Center Optical Interconnect Architecture Product Line

Shenzhen, China, July 12, 2022 – The deployment of 100G/200G data centers has greatly increased the bandwidth value-added by the development of cloud computing technology. The pursuit of the optimal 400G data center model has always been the hot spot and focus of the industry. Relying on the positioning and development of 8-channel optics, silicon photonics technology and high-speed DAC, GIGALIGHT recently announced the completion of the R&D and mass production layout of two different architectures of 400G data center product lines, which are undoubtedly designed for different user needs.

Architecture 1. Low-cost architecture based on 4-channel optics, silicon photonics technology and 100G PAM4 technology

Architecture 2. Low-latency architecture based on 8-channel optics and 50G PAM4 technology

There has been a lot of controversy about 400G data centers for some time. As the industry-wide technology in-depth exploration continues, the dust will be settled on most of the issues. Trust your judgment and let’s put faith in GIGALIGHT.

About GIGALIGHT

As the open optical network device explorer, GIGALIGHT integrates the design, manufacture and sales of active & passive optical devices and subsystems. The main products are optical transceivers, silicon photonics transceivers, liquid cooling transceivers, optical passive components, AOC & DAC, coherent optical modules and open DCI BOX subsystems. GIGALIGHT is a hardware solution provider of innovatively designed high-speed optical interconnection that focuses on data center, 5G carrier network, metro WDM transmission, UHD broadcast video and other application fields.

8Jul, 2022

Envisioning a New Era of Data Centers – GIGALIGHT 400G Silicon Photonics Wins CFCF2022 Product Innovation Award

Shenzhen, China, Jul 7, 2022 – The award ceremony of China Fiber Connect Forum ended successfully in Nanjing Huashan Hotel. GIGALIGHT once again won the annual innovation product award with its 400G QSFP DD DR4 silicon photonics.

GIGALIGHT’s core technologies for 400G silicon optical modules include high coupling efficiency package design and MZI software locking algorithms. Meanwhile, GIGALIGHT has co-designed several silicon optical waveguide chips with partners. Currently, silicon based 100G QSFP28 DR1/FR1/LR1 and silicon based 400G QSFP DD DR4/DR4+ are already in mass production.

The product strategy of GIGALIGHT’s ultra-400G data center is mainly built on the silicon photonics technology platform. To this end, the company has made relevant trade-offs in R&D and operation. GIGALIGHT believes that the combination of silicon photonics technology and 100G PAM4 technology can obtain more stable performance and long-term scalability for data center networks. At the same time, as an innovative technology, the investment in silicon photonics technology and platforms must have a tortuous process, but the investment in silicon photonics could be a national plan globally.

GIGALIGHT has received strong support from the supply chain and other industry colleagues in the development of silicon photonics technology for several years. May we, in the spirit of altruism, abandon the profit-seeking tendencies, and push an important business to a world-leading level.

Great thanks to China Fiber Connect Forum for witnessing the torrent of silicon light development with GIGALIGHT!

About GIGALIGHT

As the open optical network device explorer, GIGALIGHT integrates the design, manufacture and sales of active & passive optical devices and subsystems. The main products are optical transceivers, silicon photonics transceivers, liquid cooling transceivers, optical passive components, AOC & DAC, coherent optical modules and open DCI BOX subsystems. GIGALIGHT is a hardware solution provider of innovatively designed high-speed optical interconnection that focuses on data center, 5G carrier network, metro WDM transmission, UHD broadcast video and other application fields.

5Aug, 2021

GIGALIGHT will Share the Latest R&D Results of 400G Silicon Optical Transceivers at CIOE 2021

Shenzhen, China, August 5, 2021 − Invited by the CIOE conference, GIGALIGHT will share the technology exploration fruits of silicon optical transceivers at the Optical Transceivers & Silicon Photonics Forum of CIOE 2021 on September 2 and will demonstrate a 400G QSFP DD DR4 silicon optical transceiver at GIGALIGHT’s booth at CIOE exhibit.

It is almost a definite situation that Silicon Photonics 400G transceivers will enter in the Internet industry. Since 2020, several manufacturers have announced their successful research and development of silicon optical transceivers. GIGALIGHT has tested many silicon optical transceiver products, including its self-developed 400G DR4 and items from the competing brands, the testing results are all good. Meanwhile, GIGALIGHT also compared the results with that of the the 400G DR4 optical transceiver based on EML TOSA synchronously, those study data will be all opened to public on CIOE Optical Transceivers & Silicon Photonics Forum.

As early as 2016, GIGALIGHT cooperated with CFOL to promote the silicon optical business, and also undertook the major project of the Shenzhen Municipal Government focusing on the development of silicon optical chips. However, the project process was affected by the patent issue with US later. GIGALIGHT didn’t stop its step to explore the new technology due to the incident, but grows to a more powerful and mature enterprise under great pressure. Now, the development of Silicon Photonics is just unfolding, and the brighter future needs the joint effort of all industry participants!

GIGALIGHT will release a series of silicon optical products that can be mass-produced after 2022 successively, including:

100G QSFP28 DR1
400G QSFP DD DR4 lite /DR4/DR4+
800G QSFP DD DR8
800G OSFP DR8

About GIGALIGHT

As the open optical network device explorer, GIGALIGHT integrates the design, manufacture and sales of active & passive optical devices and subsystems. The main products are optical transceivers, silicon photonics transceivers, liquid cooling transceivers, optical passive components, AOC & DAC, coherent optical modules and open DCI BOX subsystems. GIGALIGHT is a hardware solution provider of innovatively designed high-speed optical interconnection that focuses on data center, 5G carrier network, metro WDM transmission, UHD broadcast video and other application fields.

25Jun, 2021

The 400G QSFP-DD LR8 Optical Module designed by GIGALIGHT won the CFCF 2021 Product Innovation Award!

Shenzhen, China, June 25, 2021 − The first Yangtze River Delta Optical Communication Industry Summit Forum with the theme of “Optical Linking Everything, Colorful Future” was grandly held in Suzhou on June 23-25. At the meeting, GIGALIGHT’s 8-channel optical design 400G QSFP-DD LR8 optical module won the “2021 Innovative Product Award” in the optical module category for its outstanding product performance and unique architecture design.

Subvert Tradition, Breakthrough Innovation

GIGALIGHT 400G QSFP-DD LR8 is a hot-pluggable optical transceiver module, using a single PCB design. The power consumption is less than 12W under three temperature conditions, which is at the leading level in the industry. At the same time, the product has excellent signal integrity and photoelectric integrated design. Due to the 50G PAM4 CDR based on DSP technology, the product has excellent performance and fully meets the application of single-mode dual-fiber G.652 transmission for 10km.

The product innovation points mainly include:

The self-developed 8-channel wavelength division optical engine design can greatly improve the productivity and reliability.
Single PCB high-density circuit design, which is the pioneer in the industry, and at the same time proves the signal integrity design ability.
The conceptual architecture of the 8-channel optical module was formally proposed, which poses challenges and differences to the industry’s traditional 4-channel optical module.

Because the relevant design of this module has achieved the industry-leading performance (including power consumption), it is selected by the jury, and we are deeply honored to be here!

About GIGALIGHT

As the open optical network device explorer, GIGALIGHT integrates the design, manufacture and sales of active & passive optical devices and subsystems. The main products are optical transceivers, silicon photonics transceivers, liquid cooling transceivers, optical passive components, AOC & DAC, coherent optical modules and open DCI BOX subsystems. GIGALIGHT is a hardware solution provider of innovatively designed high-speed optical interconnection that focuses on data center, 5G carrier network, metro WDM transmission, UHD broadcast video and other application fields.

30Oct, 2019

The Emergence of New Technologies Has Led Data Centers to On-Board Optical Interconnects

Due to the open structural space, the prospect of on-board optical interconnection is bright. The iteration of technology allows miniaturized and low-power pluggable optics to eventually be replaced by Consortium for On-Board Optics (COBO) or Co-Package Optics (CPO). In the future, on-board optical interconnects will dominate the major markets in the data center.

The Technical Difficulties of 100G PAM4 Hinders the Development of 400G Pluggable Optics

The 50G PAM4 can be widely applied, but not the 100G PAM4 (with DSP) currently. It is expected that a perfect system will be designed to make the 100G PAM4 widely applied, however, the specific requirements of the 100G PAM4 technology for random noise and channel have forced it to choose a trusted and limited application area.

About 100G PAM4, there are only two applications that can be guessed at present: to be used for short-distance interconnections with Silicon Photonics optics; to be used for medium-long distance interconnections (2-10km) with optimized EML lasers.

The data center must leap from 200G to 400G. Currently, only pluggable optis based on Silicon Photonics technology can realize the internal interconnection of 400G data center. We all hope that the 400G pluggable optics based on mature EML technology can quickly replace the application of 100G optics. However, the technical difficulties of 400G Silicon Photonics pluggable optics (such as 400G DR4 modules) are very huge. The 400G technical difficulties mentioned here include random noise and signal integrity, as well as heat and EMC brought by the container model of the data center. The next generation of 400G data centers have to consider more complex technical interference. These technical factors exist both in the macro and in the micro.

For long-distance data center interconnections, we suspect that 100G PAM4 should be feasible, and at least 100G Single Lambda 10km should be successful. However, it is still unclear whether this application is commercially convenient and cost-effective.

The Best Choice for 400G Data Center: On-Board Optical Interconnects

New technologies are no longer applicable to the popular mainstream architecture and major products, because any new technology has its own room for reproduction. It is foreseeable that the data center and 5G will move towards a completely different space in the application of new technologies.

For the new technology, the best case will be 100G PAM4 and Silicon Photonics combine to achieve a data center based on on-board optical interconnect. Perhaps, starting with the 400G, the data center can directly enter the on-board era. There is nothing wrong with this. After all, after getting smaller and smaller, it must be the opposite of the object, from the singularity to the open space. The future of the data center is here.

For optical module manufacturers, it is necessary to integrate into the systematic design of the data center, bid farewell to the era of plug and play and listen to the call of new technology. For modular companies with sufficient investment and proven skills in the field of nonlinear optics, on-board data centers are an excellent example of design capabilities.

Mature data centers will still experience 200G applications for a long time. Relying on the various product and architecture designs of the 400G, there is currently a lack of inspiration and guidance, so it will take a long time and a huge cost.

Obviously, the industry’s limitations and short history of data centers still lack of precipitation for the development and application of new technologies. After experiencing the subversion of optical devices, according to the current logic, the data center should give way to 5G to continue to lead the development of optical communication. In fact, as long as the data center continues 200G layout, the development and contribution of the data center to optical communication will not be lost to 5G. After all, the current maximum rate of 5G backhaul is only 200G.

Conclusion

The data center needs to calm down and complete the learning curve like any other industry, and then plan a new leap forward. Pluggable optics are used in local applications because on-board optics will go into history, but this will not hinder our confidence in pluggable continuous development and market applications. Companies with the ability to do so must hold two swords: pluggable and on-board.

30Jul, 2019

The Evolution Path of Next Generation Data Center’s Optical Interconnection

As a global innovator of optical interconnect design, Gigalight is committed to providing customers with design- and cost-leading high-speed optical interconnect product solutions. Deeply immersed in the field of optical interconnects for more than a decade, Gigalight believes that the upgrade path for next-generation data center optical interconnects should be from 100G to 200G, and then to 400G. Only such smooth upgrades and technological transitions are met the law of market development.

From 100G to 400G, the data center’s network architecture should be firstly upgraded to the most cost-effective 200G SR8/PSM8 architecture (8x 25G NRZ), then to the first generation 400G network architecture—400G PSM8/FR8 (8x 50G PAM4); and at last to the second generation 400G network architecture—400G DR4/FR4 (4x 100G PAM4). Among them, the 200G (8x 25G NRZ) network adopts the mature 25G NRZ electric chip and optical device, which has the same port density as the 100G network, but the bandwidth is doubled, which effectively reduces the transmission cost. In addition, the industrial chain of 25G NRZ optoelectronic chips and optical devices is relatively mature, and the related switches and optical module products are also easier to develop (compared to 50G PAM4), which can help the data center to quickly realize the commercial deployment of 200G networks.

At present, some companies believe that the data center network architecture should be directly upgraded to the second generation 400G, namely the 400G DR4/FR4, so they are rushing to introduce Single Lambda 100G (100G PAM4) or 400G (4x 100G PAM4) optical modules. However, these optical modules require expensive optical components, including Silicon Photonics modulators, EML lasers, and DSP error correction chips. Gigalight believes that it is too early to deploy the 400G DR4/FR4 network architecture in the data center, because the 400G DR4/FR4 products based on Single Lambda 100G PAM4 DSP technology is likely to be out of the Shannon limit, but the 400G PSM8/FR8 products based on 50G PAM4 technology are more likely to meet R&D expectations. The first generation of 400G network (8x 50G PAM4) is easier to commercialize because it adopts 8 channels of 25G linearity optoelectronic chips and related optical devices consistent with the 200G network, except that PAM4 modulation technology is used to achieve doubled bandwidth, and it is just after the 200G NRZ network in the data center network upgrade path.

The network upgrade of the data center should follow the market rules, and there is no such thing as a shortcut to the sky. Gigalight follows the rules of the market, and the 200G (8x 25G NRZ) products that are preferred for data center customers have been validated by North American data center customers. With full R&D design and verification, Gigalight now offers a complete and reliable 200G optical interconnect solution (including the 200G 4x 50G PAM4 series) with the following key benefits in smooth transition to 400G:

Low Power Consumption. With existing 25G NRZ optics, power consumption is as low as 4 watts, while optical modules based on DSP CDR technology can be 2 to 3 watts higher. In this case, saving 2 to 3 watts per 200G optical module is very beneficial for optimizing OPEX and cooling efficiency.
Low Latency. Excellent performance in some special application scenarios such as High Performance Computing (HPC) and High Frequency Trading (HFT).

The 8x 25G NRZ reduces the complexity and design difficulty of the 200G optical module and avoids the development cost and material cost of the difficult DSP. At a broader market level, 100G optical modules have matured and component integration has been established. Similarly, 200G optical modules will also form a cost structure similar to 100G optical modules in the first few years before entering the market, following the downward cost curve. Due to further standardization and automation of component integration and mass production, 200G optical modules are expected to achieve a cost structure comparable to today’s 100G optical modules. Gigalight’s breakthrough in optical packaging technology enables density increases, enabling 200G networks to be quickly and economically deployed commercially!