30 July 2025

Sumitomo Electric Industries, Ltd., in collaboration with Xtreme-D Inc. has successfully demonstrated dynamic GPU allocation to multiple servers by switching optical path using our developed optical circuit switch control software. These results will be exhibited at the JANOG56 Meeting to be held in Matsue City, Shimane Prefecture, from July 30 (Wednesday) to August 1 (Friday).

Recently, graphics processing units (GPUs)*¹ used for generative AI technology have been achieving higher performance; however, the increase in heat dissipation has become an issue, and there is also a need to enhance operational efficiency. To address these issues, our company aims to realize a composable disaggregated infrastructure (CDI)*² that can efficiently utilize GPUs while physically separating them from computing resources such as central processing units (CPUs), memory, and storage devices, which are currently predominantly integrated on a single board and electrically connected to one another. In this demonstration, we have proven that CDI can be realized by optically converting the signals connecting the CPU and GPU using an optoelectronic conversion card.
 

Furthermore, in this demonstration, two servers were connected to a GPU expansion box in a commercial data center using an optical circuit switch to confirm that GPUs can be dynamically allocated according to the needs of each server. The communication protocol between the servers and the GPU expansion box uses PCIe signals*³. The operation was verified with the distance between them set to 2 m and 1 km.

It is expected that GPUs will require new facilities with advanced cooling capabilities, such as liquid cooling systems. Through optically converting the signals, it becomes possible to separate the GPUs from the computing resources by about 1 km, allowing only the GPUs to be housed in the new facility. This significantly reduces the space required for the new facility compared to the conventional method of housing the entire server, thereby enabling reduced capital investment.

In addition, since optical circuit switches are communication signals agnostic, it can accommodate new communication standards’ signals that may emerge with future improvements in server and GPU performance.

We will continue to actively pursue our efforts to conduct demonstrations of CDI utilizing optical circuit switches and contribute to creating a data processing environment that addresses the growing demand for AI through the practical application of optical circuit switch control software.

The equipment used in the demonstration consists of servers provided by Xtreme-D, a silicon photonics optical circuit switch provided by the National Institute of Advanced Industrial Science and Technology (AIST), Japan, and PCIe transmission cards*⁴ manufactured by Dolphin Interconnect Solutions AS. Additionally, the four PCIe optical signal lanes are coupled into a wavelength multiplexer and transmitted over a single optical fiber, efficiently utilizing the connection port of the optical circuit switch. These devices are integrated and managed by our optical circuit switch control software, as well as Xtreme-D's ‘Raplase,’ a multi-cloud and high-speed AI platform service.

Overview of the Demonstratio

Demonstration  Details	Demonstration of dynamic GPU allocation to multiple servers  utilizing optical path switching with optical circuit switches
Location	Commercial data center
Period	July 14 (Monday) to July 29 (Tuesday), 2025

Overview of JANOG56 Meeting

Dates	July 30 (Wednesday) to August 1 (Friday), 2025
Venue	Kunibiki Messe (Matsue City, Shimane Prefecture)
Exhibition Location	Booth number : 120
Official Website	https://www.janog.gr.jp/meeting/janog56/

Comment from Naoki Shibata, Founder, CEO of Xtreme-D Inc. :
“We are very interested in Sumitomo Electric’s efforts to promote CDI technology through this demonstration. As a provider of AI/HPC platform services to our customers, we expect that this solution will be an important component in our GPUaaS offering, which leverages cost-effectiveness, performance, and the benefits of dynamic component switching, and we look forward to its early market launch. We are supporting the research and development of this technology for the continued development of services in combination with our AI/HPC platform service ‘Raplase.’"

Comment from Kazuhiro Ikeda, Deputy Research Director of Photonics-Electronics Integration Research Center, AIST:
“AIST is advancing the research and development of optical circuit switches based on silicon photonics to realize power-saving data centers and AI clusters, utilizing its state-of-the-art 300-mm silicon photonics prototyping line. AIST hopes that this demonstration with its silicon photonics switch that features communication standard independence, high integrability, and high speed, will accelerate the deployment of highly efficient AI processing systems utilizing optical switches. AIST will continue to work on the research and development of related technologies in cooperation with a wide range of companies and organizations, aiming to strengthen Japan's industrial competitiveness.”

Hugo Kohmann, CEO of Dolphin Interconnect Solutions AS:
“We are proud that our PCIe transmission cards have played a key role in supporting Sumitomo Electric’s challenge to realize the new AI CDI. We hope that our commercialized products and the latest technologies from both the company and its partners will form a new solution that not only reduces the capital investment and running costs of numerous AI processing end-users, but also contributes to sustainable development. We remain committed to developing new technologies and promoting further innovation.”


[Glossary of Terms]
*1 GPU
Developed as a dedicated processor for graphics processing, it is now utilized for AI processing such as machine learning and deep learning, leveraging its high parallel computing capabilities

*2 CDI
Separating computing resources such as CPUs, GPUs, memory, and storage devices, allowing them to be combined as needed for computation

*3 PCIe
PCI Express (PCIe) is an interface standard that enables high-speed data communication, used for connecting devices such as GPUs and storage devices.

*4 PCIe transmission card
An expansion card for transferring PCIe signals outside the server, installed in a PCIe slot