400G backbone network is imperative: it is too difficult for commercial use
With the advent of the 5G and cloud era, ultra-broadband
has gradually become the cornerstone of the Internet of Everything in the
intelligent era. 400G, as the new generation of mainstream high-speed Ethernet
interfaces for ultra-broadband, has gradually become the basic capability of IP
network infrastructure and has begun its vigorous development. .
With the advent of the 5G and cloud era, ultra-broadband
has gradually become the cornerstone of the Internet of Everything in the
intelligent era. 400G, as the new generation of mainstream high-speed Ethernet
interfaces for ultra-broadband, has gradually become the basic capability of IP
network infrastructure and has begun its vigorous development.
Recently, at the "400G Scale Commercial Path
Analysis" roundtable forum held concurrently with the China Optical Expo
in 2021, Dr. Li Junjie, chief expert of China Telecom's optical transmission
specialty, Dr. Wang Dong, project manager and senior engineer of the Institute
of Basic Network Technology, China Mobile Research Institute, and Bai
Zhongqiang, vice president of Huawei's optical transmission field, discussed
the issue of large-scale commercial use of 400G.
400G continues to burst out of value, with great promise in
the future
With the strong drive of future broadband transmission
demand such as cloud computing, the Internet of Things, and the new Internet,
400G has gradually moved from behind-the-scenes technical research to a
commercial front-end, especially in the past two years, where it has developed
more rapidly in China. However, at present, 100G is still in its prime, 800G is
also about to move, and the volume of 400G in the middle is getting smaller.
Li Junjie believes that 400G is not a short-lived
technology, it will be the most important technology hub in the next decade.
400G technology is now mature and can achieve full coverage. Although 800G
technology is very hot recently, based on the current technology level, it is
difficult to achieve full coverage of 800G. It may be the technology of
metropolitan area network or access network.
Wang Dong said that from 2013 to the present, 100G has
experienced a life cycle of nearly ten years and has achieved great success in
commercial deployment. Although 800G is now a hot spot in the industry, from
the perspective of the industrial structure, whether it is optical devices or
optical transmission capabilities, there is still a long way to go from
commercialization and long-distance applications. 400G is the basic consensus
of operators, and it will become a very important technology for the next
generation.
As a representative of an equipment manufacturer, Bai
Zhongqiang believes that, on the whole, 400G key technologies are making
breakthroughs and are expected to reach the level of trial commercial use in
about 1-2 years. There are still many key technologies of 800G that have not
broken through, including the core devices of the laboratory that are still under
study. It is expected that 800G will have a long way to go before it can be
commercialized.
In 2010, the IEEE formally approved the IEEE 802.3ba
standard, and the operator's IP backbone network entered the era of the 100G
platform. 100G routers are widely deployed in the backbone network and
metropolitan area networks of operators. This year, the Ministry of Industry
and Information Technology proposed to promote the deployment of backbone
network 200G/400G transmission on demand. Entering the backbone network from
the metropolitan area network is also the ultimate destiny of 400G, but for
now, the road ahead for 400G is a bit bumpy.
In this regard, Li Junjie replied: If a technology wants to
be mature and commercialized, it faces the problem of cost performance, and the
cost performance is sufficient to be able to operate. Therefore, from the
perspective of performance and price, at this stage, the implementation of 400G
on the backbone network is still more difficult.
He added that, looking at it now, the single-wavelength 400G
transmission technology has certain shortcomings in the backbone network in
terms of performance. The other is cost. Cost is an unavoidable problem. 400G
has not yet been launched on a large scale. The main problem is high cost. If
the cost of 400G is higher than four 100Gs, the deployment power of operators
is insufficient in this case.
Wang Dong said that the current channel spacing based on
75GHz can basically meet the needs of the metropolitan area network, and there
is still a big gap in the demand for the backbone network for thousands of
kilometers or more than 1,500 kilometers. Only by further increasing the
transmission distance can operators better promote 400G from the metropolitan
area to the backbone network, and meet the business needs more quickly.
Upstream and downstream linkage accelerates the maturity of
the 400G industry chain
In Li Junjie's view, the 400G industry chain has basically
matured, and it has been almost ten years since the establishment of the 400G
standard. 400G applications in data centers have been three to four years, and
the industry chain is currently relatively mature. Among them, the biggest
shortcoming is the control of high-end technology.
According to him, many high-precision components are
currently in the hands of foreign companies, such as adjustable lasers, analog
and digital circuits, and so on. Hope to have Chinese manufacturers in this
field, so as to create a mature and healthy industrial chain.
Li Junjie emphasized that, first of all, it is very
important for the industrial chain to join hands. Secondly, the issue of diversification
of technical routes and the issue of non-focusing of technology should be paid
more attention to. More importantly, in terms of standardization, the entire
industrial chain needs to be interoperable as soon as possible. "As an
operator, China Telecom hopes that the standard technology can be
interconnected. China Telecom will work with suppliers to accelerate the
standard focus of 400G technology and accelerate its maturity as soon as
possible, and transform 400G technology into productivity as soon as
possible.".
Regarding the current 400G industrial chain, Wang Dong
believes that for metropolitan area networks, 400G has built a very complete
industrial chain and has the conditions for deployment. Facing the backbone
network, the equipment and equipment technical solutions of various mainstream
equipment manufacturers have been initially capable of transmission for one
thousand kilometers.
Wang Dong pointed out that operators especially hope that
the industry chain can reach a unified solution, and work together to make the
technology more mature, and the performance and price of the products are more
convenient for operators to use and deploy. He hopes to use the domestic CCSA
platform and the industry to work together to promote the development of 400G
technology. "Whether it is an optical component manufacturer, an optical
module manufacturer or an amplifier manufacturer, etc., it is necessary to have
clear index definitions and a path for research and development. This will
reduce the cost of R&D investment, and ultimately be able to focus more on
technical routes and quickly meet the needs of operators. Demand."
Bai Zhongqiang said that in the field of metropolitan area
networks, foreign industrial chains are gradually becoming mature. In contrast,
domestic companies are still under the control of others. He hopes that the
domestic industrial chain can follow up as soon as possible; in the field of
backbone networks, there is still an urgent need for breakthroughs in China.
Key technologies, including electrical layer, optical layer and system.
At the end of the round table, the three experts all talked
about the outlook for 400G technology. Li Junjie said that for 400G, he not
only hopes to be more localized in high-precision components, but also hopes
that the industry can seize the time to reserve next-generation technologies.
Wang Dong called on industry, academia and research institutes to work together
to advance the exploration of basic research on 400G applications, promote my
country's research in optical devices, optical modules, or some relatively more
cutting-edge technologies, and achieve overall results in the entire industry.
Bai Zhongqiang hopes that my country's upstream and downstream industrial chain
will increase investment and strive to become a global leader in the future.