NTT DoCoMo has unveiled a network-centric AI cluster across Japan, leveraging its all-photonic network (APN) technology to link distributed data centers. The initiative, branded as "GPU over APN," represents a significant step in the evolution of distributed computing infrastructure, aiming to reduce reliance on massive centralized data centers by enabling workloads to be spread across smaller, regional facilities powered by locally available renewable energy.
The testbed is a wide-area distributed graphics processing unit (GPU) demonstration environment built on NTT Group's Innovative Optical and Wireless Network (IOWN) concept. According to the Japanese telecom giant, APN's high-speed, low-latency optical connectivity allows distributed AI data centers to support both large language model (LLM) training and inference more efficiently. GPUs are deployed across eight locations, including Sapporo, Kanazawa, Fukuoka, and Osaka, as well as four sites in the Tokyo metropolitan area: Akihabara, Mitaka, Kawasaki, and Yokohama. These GPUs are compatible with virtual machines (VMs) and Kubernetes, and can be provided in a multitenant configuration.
NTT DoCoMo highlighted successful verification of advanced AI workloads using remote direct memory access (RDMA) to achieve 100 Gb/s connectivity. In one demonstration, the system transferred 25 gigabytes of data in just two seconds across the 621-mile distance between Fukuoka and Tokyo. This achievement underscores the potential of APN to overcome latency and bandwidth challenges that have historically limited distributed AI computing.
The move follows a separate initiative by NTT East, which partnered with Sakura Internet and Equinix Japan to connect Sakura's Ishikari data center in Hokkaido with Equinix facilities in Tokyo. Those three partners are evaluating key network metrics such as throughput and latency across a live Hokkaido-to-Tokyo connection to establish operational parameters for commercial rollout.
In a parallel development, NTT has established an "IOWN-AI" fund aimed at expanding the IOWN ecosystem. The fund was formed with Taiwanese operator Chunghwa Telecom, South Korean conglomerate SK Group, and the Development Bank of Japan, and is expected to raise approximately $500 million. Potential investors include Fujitsu, GlobalFoundries, KDDI, NEC, Samsung Electronics, and Toshiba. This financial backing signals strong industry interest in photonics-driven distributed data center architectures, which could reshape how AI workloads are deployed and managed globally.
Source: sdxcentral