The Ice and Fire of the Optical Communication Industry Chain
Despite a history of only half a century, optical fiber, with its excellent performance such as large capacity, low loss, and strong anti-interference capability, has become the core physical foundation of today's information society and will play an irreplaceable role in the foreseeable future. It is gratifying that after more than 20 years of arduous efforts, Chinese optical fiber manufacturers have mastered the core manufacturing technologies of the entire industry chain from preform to fiber to cable, and have captured half of the global market share. Optical communication is also one of the fields in China's high-tech sector closest to the world's advanced level.
Wei Leping, Executive Deputy Director of the Science and Technology Committee of the Ministry of Industry and Information Technology and Director of the Science and Technology Committee of China Telecom, is undoubtedly one of the most authoritative experts in the communications field. At this conference, Mr. Wei also attended and delivered a speech. During a break in the conference, C114 editors seized the opportunity to interview Mr. Wei, seeking his insights on the development status of optical fiber and the entire optical communication industry chain—a state of high prosperity yet with shortcomings, like ice and fire.
Optical Fiber: Issues Beyond 100G
In his speech, Wei Leping pointed out that China's backbone network reached a maximum segment capacity of 12T in 2013, with 100G beginning large-scale deployment and becoming the dominant technology in the backbone network. Indeed, with the rapid advancement of information technology, the continuous high-speed growth of bandwidth demand driven by mobile internet, big data, 4K, and even VR, along with the emergence of killer applications consuming large bandwidth, is pushing the backbone network to further upgrade. The next-generation 400G and even 1T networks have already been put on the agenda.
Networks beyond 100G require the support of a new generation of optical fiber. Therefore, a dedicated seminar on "Preparing for 400G" new-type optical fiber was held during this conference. International manufacturers such as Corning and Sumitomo, as well as domestic manufacturers including YOFC, Hengtong, and FiberHome, which have already announced the launch of new-generation optical fiber, all discussed the requirements of beyond-100G networks for new-generation fiber. In general, the focus is on two directions: ultra-low loss and large effective area. The balance and trade-off between ultra-low loss and large effective area became the focal point of discussion.
Wei Leping told C114 that both ultra-low loss and large effective area are theoretically entirely correct. Viewed separately, ultra-low loss fiber is more aligned with the actual needs of existing networks than large effective area fiber. The first reason is cost. Thanks to the efforts of companies like Corning, the price of ultra-low loss fiber has dropped to only three times that of conventional fiber. When applied to cables, it increases the cost by only 10%. Finally, when applied to the entire transmission system and network, the cost increase is less than 1%. Given that the service life of optical fiber cables is as long as 20 to 30 years, this slight cost increase is entirely acceptable. Otherwise, one would face the awkward situation of having to add many repeater stations and rework the optical cable infrastructure.
More importantly, ultra-low loss fiber can be effectively spliced with existing network fiber, with minimal splice loss, and maintenance methods and habits remain unchanged, making it well received by maintenance departments. Although large effective area fiber has undisputed advantages in combating nonlinear effects, with performance slightly better by 0.5 dB than ultra-low loss fiber, its application within the vast existing conventional fiber resources will inevitably encounter splicing issues with conventional fiber in various scenarios. Due to the mismatch in effective area, the loss is too high, requiring specially designed fusion splicers and entirely new splicing methods. It also necessitates changes to maintenance procedures and habits, increases the complexity of spare parts management, and requires retraining of maintenance personnel. These are the most undesirable issues for maintenance work. The slight benefit it brings is simply not worth the trouble of overhauling the well-established and familiar maintenance system and procedures.
Wei Leping pointed out that combining the two—ultra-low loss and large effective area—naturally yields the best performance. However, with current technology and process levels, the cost would be more than 10 times higher than conventional fiber, making it difficult to apply widely in terrestrial cable systems. It is only suitable for special submarine cable systems. He frankly stated that Corning had already produced ultra-low loss fiber six years ago, but Chinese optical fiber manufacturers did not pay sufficient attention to this, wavered in their technical direction, considered the market too small, and were slow to deliver products.
Although a few domestic manufacturers such as YOFC released ultra-low loss fiber products last year, their loss levels still lag considerably behind the advanced level. In short, the overall absence of Chinese optical fiber manufacturers in ultra-low loss fiber will directly impact the future development of China's 400Gbit/s optical fiber infrastructure network. Wei Leping's consideration of the demand for new-generation fiber based on the future practical application of existing networks is worthy of deep reflection by industry manufacturers. Fifty years after the invention of optical fiber, Chinese optical fiber manufacturers have grown in scale, but in high-end technology areas, they still need to accelerate their catch-up pace to help enhance the competitiveness of the backbone network.
Optical Components: An Urgent Need to Narrow the Gap
In the optical communication industry chain composed of optical equipment, optical fiber and cable, and optical components, Chinese companies such as Huawei, ZTE, and FiberHome have brought optical equipment to the world's advanced level, with significant influence in both domestic and international markets. The optical fiber and cable sector also demonstrates strong competitiveness. However, in the most easily overlooked field of optical components, Chinese manufacturers have remained stuck in the low-end market. Over the years, the technology gap with leading foreign manufacturers has not narrowed, becoming a major concern for the healthy operation of the industry chain.
When C114 raised this issue, Wei Leping directly pointed out that the government has not paid sufficient attention to optical components and optical chips. In the optical fiber and cable field, the government has repeatedly employed the "anti-dumping" measure, buying valuable catch-up time for domestic optical fiber manufacturers. However, in the optical component and optical chip field, the high technical threshold, small scale, and lack of large capital investment—combined with the inability of numerous small and medium-sized manufacturers in the industry to invest heavily in R&D and the absence of strong government policy support—have resulted in the current backward situation.
Wei Leping stated that he himself, along with academicians such as Zhao Zisen and other experts, had called for national support for optical component chips decades ago, but has never seen national attention and investment. "Optical component chips are extremely important. Moreover, compared with microelectronics, the gap between China's optical component chips and the international advanced level is smaller, requiring less investment and being easier to achieve breakthroughs. The country has invested hundreds of billions of yuan in microelectronics, and the recently established large fund has nothing to do with optical component chips either!"
In the field of photonic integration, which represents the future direction of optical component chips, the United States has already taken preemptive action. In July 2015, the U.S. government invested $610 million to establish the American Institute for Manufacturing Integrated Photonics (AIM Photonics). This institute organizes manufacturers, material suppliers, software providers, users, and researchers to promote collaboration and build a standardized integrated photonics platform to facilitate technology diffusion. This move reflects the U.S. government's long-term strategic vision. According to Wei Leping, China has so far no plans to establish a similar institution.
A senior industry insider once told C114 that possessing photonic integration technology is not just a means to win a particular industry market, but something a country must do to gain strategic technological competitiveness. China also needs government attention to optical component chips. Although market share is increasing, ignoring the technology gap means losing the future.
From the perspective of optical network cost composition, Wei Leping stated that optical components currently account for 50%–60% of the cost in existing equipment. As speeds continue to increase, this share could rise to 80%–90%, making it critically important. "Breakthroughs in optical component technology are truly urgent. In particular, I hope that optical component chip technologies such as quantum dot lasers and silicon photonic devices can be broken through as soon as possible, thereby helping to significantly reduce network construction costs, power consumption, and size, and providing strong component technology support for the next wave of optical network development."