April 2025 Vol. 23 No. 4

View from the Top

• Kazunori Katsura, Representative Member of the Board, Senior Executive Vice President, NTT WEST

  

  Abstract
  NTT WEST is evolving telecommunications to move with the changing times, creating new norms by connecting, and contributing to the creation of a prosperous society. As well as its mission of protecting telecommunications—round the clock, year after year—as a foundation of society, which is something that had been taken for granted, NTT WEST is creating and supporting new products and services that will be taken for granted in daily life and business. We spoke with Kazunori Katsura, senior executive vice president of NTT WEST, about the present situation and outlook for the company’s network-facilities area.

Front-line Researchers

• Kazuhide Nakajima, Senior Distinguished Researcher, NTT Access Network Service Systems Laboratories

  

  Abstract
  It is becoming increasingly necessary to expand network communication capacity to accommodate the increase in data transmission between datacenters due to the evolution of generative artificial intelligence and the increase in data transmission due to the spread of extended-reality services. To expand network-communication capacity, it is necessary to not only improve the capacity of the transmission system but also the transmission medium, namely, optical fiber. A multi-core optical fiber (MCF), in which multiple cores (i.e., the paths through which light travels along the optical fiber) are arranged spatially in a single optical fiber, has been developed, and a 12-core MCF—the world’s highest core density—is appearing. Technologies for applying optical fiber to non-communication areas, such as measuring loss by using the scattering of light passing through optical fiber, have also been developed. Kazuhide Nakajima, a senior distinguished researcher at NTT Access Network Service Systems Laboratories, is working to put 4-core MCF into practical use as soon as possible and apply MCF to non-communication areas. We talked with him about the essential technologies for deploying 4-core MCF in the field, power-over-fiber (PoF), i.e., optical-power-supply technology, using MCF, international standardization of MCF, and the importance of connection points in research and the mindset required to find and use them.

Rising Researchers

• Takumi Yokosaka, Distinguished Researcher, NTT Communication Science Laboratories

  

  Abstract
  Many tactile illusions lurk within our daily lives, such as feeling a sensation that doesn’t exist or feeling that someone else’s fingers are your own. This report hears from NTT Distinguished Researcher Takumi Yokosaka about his research into understanding the sensory experience of human beings by using these illusions and the many tactile illusions published on the Illusion Forum, an NTT website to experience such illusions.

Feature Articles: Technical Seminars at NTT R&D FORUM 2024 - IOWN INTEGRAL

• Next Generation AI

  

  Abstract
  This article presents a panel discussion on the limitations and future prospects of current large language models, which is based on a technical seminar conducted at the “NTT R&D FORUM 2024 - IOWN INTEGRAL” held from November 25th to 29th, 2024.

• The Future of Photonics-electronics Convergence Technology and Supercomputers

  

  Abstract
  This article presents a discussion on the forefront of photonics-electronics convergence technology, which is based on a technical seminar conducted at the “NTT R&D FORUM 2024 - IOWN INTEGRAL” held from November 25th to 29th, 2024.

Regular Articles

• Highly Corrosion-resistant Coatings for Steel Infrastructure in Coastal Areas

  

  Abstract
  The NTT Group possess a huge number of outdoor telecommunications facilities composed of metallic materials or painted metallic materials, such as mobile-phone base-station towers, as part of the important infrastructure that supports telecommunications services. An increasing number of steel towers have become in need of anti-corrosion coating as their zinc layer of galvanized steel has been worn away by corrosion. Anti-corrosion coating deteriorates after 12 years or so and requires reapplying. Therefore, we are developing a long-lasting, corrosion-resistant paint to reduce the cost of repainting towers by extending the interval between reapplying anti-corrosion coating.
  We are developing a zinc-rich paint (ZRP) that exhibits higher corrosion-protection performance than conventional ZRP in coastal areas (where corrosion is likely to progress due to the inflow of sea-salt particles by wind) and optimizing the coating specifications (i.e., combinations of paint coats) that include this ZRP. The results of an experimental evaluation of the developed ZRP, the performance of which was improved by adding an additive to a commercially available ZRP, and the results of a study on optimizing coating specifications that include ZRP according to the installation environment and type of steel structure are presented in this article.

Global Standardization Activities

• Latest Trends in Network API Standardization: GSMA Open Gateway and CAMARA Project

  

  Abstract
  The CAMARA project, in collaboration with GSMA Open Gateway, aims to accelerate third-party service provider’s access to telecommunication-operator-network functions by developing standardized, operator-agnostic application programming interface (API) specifications. This article provides an overview of the rationale behind this API standardization, partnership between the CAMARA project and GSMA Open Gateway, and unique characteristic and methodologies of the CAMARA project and outlines NTT’s future work within the project.