NTT IOWN and the 6G Race: Why the Next Internet May Be Built in Japan

While much of the world focuses on squeezing more performance out of 5G networks, Japan’s largest telecommunications company is quietly engineering something far more ambitious. NTT’s IOWN initiative — a full rethinking of internet infrastructure built on photonics rather than electronics — could position Japan at the center of the global 6G race. With a 2030 target for commercial deployment and billions of dollars in R&D investment, the next internet may indeed be built in Japan.

The IOWN Vision: An All-Photonics Network

In 2019, Nippon Telegraph and Telephone Corporation (NTT) unveiled IOWN — the Innovative Optical and Wireless Network. At its core, IOWN proposes replacing the electronic switching and routing that underpins today’s internet with an end-to-end photonics-based infrastructure. The implications are staggering: latency reduced by a factor of 200, energy consumption cut by 100 times, and transmission capacity 125 times greater than current networks.

IOWN rests on three technological pillars. The first is the All-Photonics Network (APN), which transmits data as light from end to end — eliminating the optical-electrical-optical conversions that create bottlenecks in current fiber networks. The second is Digital Twin Computing, which creates high-fidelity virtual replicas of physical systems for real-time simulation and prediction. The third is Cognitive Foundation, an AI-driven orchestration layer that dynamically manages network resources across heterogeneous infrastructure.

NTT has not pursued this vision alone. In 2020, the company co-founded the IOWN Global Forum with Intel and Sony, an organization that has since grown to include more than 130 member companies spanning telecommunications, semiconductors, cloud computing, and enterprise IT. This coalition approach reflects a strategic calculation: building the next-generation internet requires collaboration across the entire technology stack.

Photonic Computing: The Hardware Revolution

Perhaps the most radical element of IOWN is the push toward photonic computing — processing data with light rather than electrons. NTT’s research laboratories have demonstrated photonic transistors and optical logic gates that operate at speeds fundamentally impossible for silicon-based electronics. In March 2024, NTT announced a breakthrough in photonic-electronic convergence chips that integrate optical and electronic circuits on a single substrate, a critical step toward commercially viable photonic processors.

The energy implications alone could reshape the economics of data centers. Current estimates suggest that global data centers consume roughly 1-1.5% of worldwide electricity, a figure projected to rise sharply with the proliferation of AI workloads. Photonic computing promises to decouple computational growth from energy consumption — a proposition that has attracted interest from hyperscale cloud providers increasingly concerned about their carbon footprints.

Japan’s 6G Roadmap: Targets and Timelines

The Japanese government has placed 6G at the center of its technology strategy. In 2020, the Ministry of Internal Affairs and Communications (MIC) published its “Beyond 5G Promotion Strategy,” outlining a comprehensive roadmap for 6G development with commercial deployment targeted for 2030. The strategy identifies six key performance indicators that define Japan’s 6G ambition.

Sources: Ministry of Internal Affairs and Communications, “Beyond 5G Promotion Strategy” (2020); ITU-R Future Technology Trends (2023)

To support this ambition, the Japanese government has committed substantial funding. The Beyond 5G Fund, established in 2021, allocated approximately ¥200 billion (roughly $1.5 billion) for R&D in next-generation communications technologies. Additional funding has flowed through the National Institute of Information and Communications Technology (NICT), which serves as the primary government research body for telecommunications innovation.

Terahertz Communication: The Frequency Frontier

One of the most technically challenging aspects of 6G is the exploitation of terahertz (THz) frequencies — the electromagnetic spectrum between 100 GHz and 10 THz. These frequencies offer enormous bandwidth but present formidable propagation challenges, including high atmospheric absorption and limited range. Japanese researchers have been at the forefront of addressing these limitations.

NICT demonstrated a 6G prototype in late 2023 achieving data rates exceeding 100 Gbps using frequencies in the 300 GHz band. NTT has separately demonstrated indoor terahertz communication at distances sufficient for practical deployment in enterprise environments. The path from laboratory demonstration to commercial product remains long, but Japan’s early achievements in terahertz research have established a foundation of intellectual property that will shape global 6G standards.

KDDI and SoftBank: The Carrier Competition

KDDI, Japan’s second-largest mobile carrier, has pursued 6G research with a particular emphasis on satellite-terrestrial integration. The company envisions a network architecture where low-earth orbit (LEO) satellite constellations work seamlessly with ground-based infrastructure to provide ubiquitous connectivity — including in rural areas and maritime environments where terrestrial coverage is impractical. In 2023, KDDI and SpaceX’s Starlink launched a partnership to bring satellite-to-mobile connectivity to Japan, a stepping stone toward the fully integrated networks envisioned for the 6G era.

SoftBank has taken a different approach, investing heavily in high-altitude platform stations (HAPS) — solar-powered, unmanned aircraft that fly in the stratosphere and function as floating cell towers. Through its subsidiary HAPSMobile (now rebranded as part of SoftBank’s broader technology organization), the company has conducted flight tests and aims to deploy HAPS commercially as a complement to terrestrial 6G networks. SoftBank has also been active in sub-terahertz research, collaborating with Samsung on prototype systems operating in the 100-300 GHz range.

Rakuten Mobile, the disruptive newcomer to Japan’s mobile market, has contributed a different kind of innovation. Its fully virtualized, cloud-native mobile network — the world’s first — has demonstrated that carrier-grade telecommunications can be built on software-defined infrastructure. This architectural philosophy aligns closely with the 6G vision of programmable, intelligent networks and has attracted attention from operators worldwide through Rakuten Symphony, the company’s infrastructure export arm.

The Global 6G Race: How Japan Compares

Japan does not pursue 6G in isolation. The race to define and deploy next-generation wireless communications is genuinely global, with significant programs underway in the United States, European Union, China, and South Korea. Understanding Japan’s competitive position requires examining each rival’s strategy and investment.

Sources: ATIS Next G Alliance (2023); European Commission Horizon Europe; MSIT Korea 6G Strategy (2023); MIC Japan Beyond 5G Fund reports; industry analyst estimates

China’s investment scale is difficult to verify precisely, but the country’s track record in 5G deployment — where it built more base stations than the rest of the world combined — suggests its 6G ambitions should be taken seriously. South Korea, which was first to deploy commercial 5G in 2019, has signaled an aggressive 6G timeline with Samsung and LG leading private-sector research. The United States, through the Next G Alliance convened by ATIS, has emphasized open and interoperable architectures, while the European Union’s Hexa-X project focuses heavily on sustainability and energy efficiency.

Japan’s Differentiators

Japan’s competitive advantages in the 6G race are distinctive. First, the depth of NTT’s photonics research is unmatched globally — no other entity has committed as comprehensively to an all-photonics paradigm. Second, Japan’s strength in advanced materials science and precision manufacturing gives it a natural advantage in producing the exotic components required for terahertz and photonic systems. Third, the relatively coordinated relationship between Japan’s government, carriers, and equipment manufacturers enables faster alignment on standards and deployment strategies than is typically possible in more fragmented markets.

The risk, however, is that Japan’s telecommunications equipment industry has lost global market share over the past two decades. Whereas NEC and Fujitsu were once major players in mobile infrastructure, today’s market is dominated by Ericsson, Nokia, and Huawei. Japan’s 6G strategy must contend with the challenge of translating research leadership into commercial products that achieve global adoption.

Business Opportunities in Japan’s 6G Ecosystem

For international companies, Japan’s 6G push creates several categories of business opportunity. The most immediate is participation in the IOWN Global Forum and related standards bodies, where the technical specifications that will govern next-generation networks are being drafted. Companies that contribute to these standards gain early insight into technology directions and the ability to shape specifications in ways that align with their product roadmaps.

The photonic component supply chain represents a particularly compelling opportunity. IOWN’s all-photonics vision requires vast quantities of optical transceivers, photonic integrated circuits, optical amplifiers, and related components. While Japanese companies like Sumitomo Electric and Furukawa Electric are strong in optical fiber, the broader photonic component ecosystem remains fragmented and open to international suppliers.

Vertical applications of 6G technology offer another entry point. Industries such as autonomous driving, remote surgery, holographic communication, and industrial metaverse applications require the extreme low latency and high bandwidth that 6G promises. Companies developing solutions in these domains will find eager partners among Japan’s carriers and enterprise customers, who are actively seeking use cases to justify the enormous infrastructure investment 6G requires.

The Regulatory Landscape

Japan’s regulatory framework for next-generation telecommunications is evolving rapidly. The MIC has signaled a more open approach to spectrum allocation for 6G, recognizing that the terahertz bands required for next-generation services will demand new licensing paradigms. International companies should monitor developments at the MIC and engage with the Ministry of Internal Affairs and Communications through its public consultation processes.

Additionally, Japan’s participation in international standards bodies — particularly the International Telecommunication Union (ITU) and 3GPP — provides a multilateral channel for engaging with Japanese 6G stakeholders. The ITU’s IMT-2030 framework, which will formally define 6G requirements, is expected to be finalized by 2027, setting the stage for the detailed technical standardization that will follow.

Looking Ahead: The 2030 Horizon

The timeline for 6G commercialization — broadly consensus around 2030 — means that the strategic decisions being made today will determine the competitive landscape for decades. Japan’s approach, anchored by NTT’s IOWN vision and supported by substantial government investment, represents one of the most coherent national 6G strategies in the world.

Whether Japan can translate this strategic clarity into commercial success will depend on execution. The country must overcome several challenges: scaling photonic manufacturing to the volumes required for mass deployment, attracting and retaining the specialized talent needed for photonics and terahertz research, and building international alliances that extend the reach of Japanese technology beyond domestic markets.

The stakes are high. The country or consortium that defines 6G infrastructure will shape the digital economy for the 2030s and beyond — influencing everything from AI computation to autonomous mobility to immersive media. Japan has placed a substantial and well-considered bet. The next five years will determine whether it pays off.

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