Joint proposal by NTT, KDDI, Fujitsu, NEC, and Rakuten Mobile adopted as Japan’s Ministry of Internal Affairs and Communications/NICT’s “Innovative ICT Fund Projects for Beyond 5G/6G” for social implementation and overseas expansion oriented strategic pro

The Need for Advanced Network Infrastructure in the Beyond 5G/6G Era

The evolution from 5G to Beyond 5G and 6G networks is expected to dramatically increase society’s reliance on information and communications technology. This shift will demand unprecedented data transmission capacity, ultra-low latency, and enhanced processing speeds to support emerging applications such as artificial intelligence, immersive digital experiences, and massive IoT deployments.

Traditional communication networks face challenges in scaling to meet these requirements, especially in terms of energy efficiency and fault tolerance. As Japan pursues carbon neutrality, reducing power consumption in network infrastructure has become a critical priority. All-photonics networks (APNs), which leverage optical technologies for data transmission, offer a promising solution by enabling high-speed, low-latency communication with significantly lower energy use compared to electronic counterparts.

Recognizing these needs, Japan’s Technology Strategy Committee and the All-Optical Network Common Infrastructure Technology Working Group have emphasized the importance of developing APNs that can interconnect multiple sites and providers seamlessly. Their reports in mid-2024 outlined the strategic direction for APN development, highlighting the necessity for multi-provider cooperation and flexible network architectures.

Collaborative Research and Development by Japan’s Telecom and Tech Leaders

In response to the call for innovation, NTT Corporation, KDDI Corporation (along with KDDI Research), Fujitsu Limited, NEC Corporation, and Rakuten Mobile jointly submitted a proposal to NICT’s Beyond 5G (6G) Fund Project. Their proposal was selected in October 2024 as part of a strategic program focused on social implementation and overseas expansion of common infrastructure technologies.

This collaborative effort combines the expertise of Japan’s leading telecommunications carriers and technology providers to develop an APN architecture that supports multi-provider federation and flexible user connectivity. The project’s scope includes enabling users to access multiple cloud data centers simultaneously and switch connection destinations dynamically without compromising service quality or reliability.

A key innovation is the development of a small APN node designed for deployment in regional data centers and smaller sites. This downsized node will facilitate the expansion of APNs beyond major urban centers, supporting rural areas and medium-sized enterprises, thereby promoting more inclusive digital infrastructure.

Core Technologies Under Development

The research and development activities are structured around three main technical components:

1. Photonic Network Federation Technology: This involves creating application programming interfaces (APIs) that accept user communication requests and manage stable interconnections between APNs operated by different carriers. The technology ensures that communication parameters such as destination, quality, and reliability are met according to user needs.

2. Subchannel Circuit Exchange Technology: This technology enables the simultaneous use of multiple clouds and data centers by accommodating numerous users while maintaining communication quality metrics like bandwidth, delay, and jitter on an end-to-end basis. It supports flexible switching between connection points to optimize network performance and user experience.

3. Distributed Reconfigurable Optical Add Drop Multiplexing (ROADM) Technology: ROADM nodes are essential for managing optical wavelengths in a network. The project aims to develop a simplified ROADM interface that allows network nodes to operate with only partial functionalities (such as wavelength insertion, branching, and multiplexing), enabling the creation of smaller, more cost-effective APN nodes. These nodes can be deployed in less centralized locations and cooperate with full-function ROADM nodes to maintain network integrity.

Potential Societal and Economic Impacts

The successful implementation of this project promises to transform Japan’s telecommunications landscape by enabling seamless, high-speed, and resilient connectivity across multiple providers. Users will benefit from the ability to connect simultaneously to various cloud and AI service providers with low latency and high reliability, facilitating advanced digital services and applications.

Moreover, the deployment of smaller APN nodes in rural and medium-sized data centers will help bridge the digital divide, ensuring that remote and less densely populated areas receive improved network services. This inclusivity supports regional economic development and enhances access to digital resources nationwide.

From an environmental perspective, the energy efficiency gains from photonics-based networks align with Japan’s carbon neutrality goals. Reducing power consumption in communication infrastructure is vital as data traffic and processing demands surge in the Beyond 5G/6G era.

Internationally, the project’s focus on overseas expansion indicates Japan’s ambition to lead in next-generation network technologies, potentially influencing global standards and fostering new markets for APN solutions.

Challenges and Future Outlook

While the project holds significant promise, several challenges remain. Integrating APNs across multiple providers requires robust coordination and standardization to ensure interoperability and security. Managing complex network architectures with dynamic user demands will necessitate sophisticated control algorithms and real-time monitoring.

Furthermore, scaling the technology from research prototypes to widespread commercial deployment involves overcoming technical, regulatory, and economic hurdles. Ensuring that smaller APN nodes maintain performance and reliability comparable to larger installations is critical.

Nevertheless, the collaboration among Japan’s top telecom and technology firms, backed by government support, provides a strong foundation for addressing these challenges. The project’s outcomes could set a precedent for future network infrastructure development worldwide, particularly as digital transformation accelerates globally.

What this means

The joint initiative by Japan’s leading telecommunications and technology companies to develop an all-photonics network infrastructure marks a significant step toward realizing the full potential of Beyond 5G and 6G technologies. By enabling seamless multi-provider cooperation, flexible user connectivity, and energy-efficient network operations, this project addresses critical demands anticipated in the coming era of digital transformation. While technical and operational challenges remain, the collaborative approach and government backing provide a robust framework for success. The outcomes of this research and development effort will not only enhance Japan’s domestic digital infrastructure but also contribute to shaping global standards and practices in next-generation communication networks.