SINGAPORE, April 14, 2025 – In a landmark moment for next-generation data centre networks, Keysight Technologies, NTT Innovative Devices Corporation, and Lumentum Holdings Inc. have jointly achieved a new benchmark in optical data transmission, successfully demonstrating 448 Gbps data throughput using 224 GBaud PAM4 technology at this year’s Optical Fiber Communication Conference and Exhibition (OFC) 2025.
This technical milestone lays the groundwork for the development of 3.2 terabit (Tbps) optical interfaces—designed to meet the surging demand from artificial intelligence (AI) and machine learning (ML) applications that require lightning-fast, real-time data transfer across compute and networking environments.
With data centres at the heart of digital infrastructure and AI workloads growing exponentially, this achievement comes at a critical time. By enabling ultra-high-speed data movement with lower power consumption, the new transmission rate not only accelerates performance but also offers meaningful gains in energy efficiency—an increasingly important consideration for hyperscalers and cloud providers.
Driving the AI Revolution with 448 Gbps Optical Transmission
At the core of this demonstration were two Keysight M8199B Arbitrary Waveform Generators, operating in tandem with NTT’s proprietary frequency-domain interleaver to generate 448 Gbps electrical signals at 224 GBaud PAM4. These signals were then transmitted using Lumentum’s cutting-edge indium phosphide (InP) externally-modulated laser (EML), creating a robust and efficient optical data stream optimised for future data centre networks.
The same hardware setup also successfully demonstrated the generation of 240 GBaud PAM4 signals—an additional nod to the scalability of the technology for future upgrades.
“AI and ML aren’t just buzzwords—they’re reshaping industries,” said Dr Joachim Peerlings, Vice President of Network and Data Centre Solutions at Keysight Technologies. “This demonstration underlines how Keysight, together with NTT and Lumentum, is actively enabling the infrastructure required to support this transformation. Our mission is to help the industry unlock the next level of speed, reliability, and energy efficiency in data communication.”
Technical Innovations Behind the Breakthrough
The joint demo showcased the capabilities of a full suite of high-performance instruments, including:
- Keysight M8199B Arbitrary Waveform Generator, capable of 256 GSa/s sampling rate and over 80 GHz of analogue bandwidth—the fastest in its class.
- Keysight N1032A DCA-X Sampling Oscilloscope, designed for precise analysis of high-baud-rate optical signals with up to 120 GHz of optical bandwidth.
- NTT’s frequency-domain interleaver, commercialised as Keysight M8159A, enhancing signal generation capabilities.
- Lumentum’s InP externally-modulated laser (EML), a core component in enabling low-power, high-speed optical transmission.
Dr Akimasa Kaneko, Executive Vice President of the Photonic Component Business Group at NTT Innovative Devices, emphasised the significance of this step forward: “We believe we’ve laid the foundation for 400G per lane communications, and we’re proud to contribute to advancing the infrastructure necessary to support the future of AI.”
Dr Matthew Sysak, Chief Technology Officer for Cloud and Networking Platforms at Lumentum, echoed the sentiment: “This is more than just a speed record. It’s a validation of our ability to deliver scalable, high-performance optical solutions that empower data centres to keep up with AI’s insatiable demand for data.”
A Turning Point for Data Centre Design
With AI and ML workloads expected to dominate data centre traffic in the coming years, this joint demonstration signals a paradigm shift in how networks are architected and scaled. The 448 Gbps benchmark significantly boosts the efficiency of inter-node communication within data centres, allowing for larger AI models and more sophisticated machine learning algorithms to be deployed without bottlenecks.
Moreover, the focus on power efficiency aligns with growing industry efforts to reduce the environmental impact of sprawling data infrastructure. By leveraging PAM4 modulation and advanced photonic components, the collaborative effort between Keysight, NTT, and Lumentum is shaping a future where performance and sustainability go hand in hand.
The M8199B AWG and N1032A/B DCA-X Sampling Oscilloscopes used in the demo are integral to Keysight’s AI-focused portfolio, known as Keysight Artificial Intelligence (KAI)—a suite of end-to-end solutions designed to accelerate and optimise AI processing in modern data centres.
As the digital world moves into an AI-first era, innovations like these form the bedrock of a more connected, efficient, and intelligent infrastructure.