400Gbps/800Gbps IOWN APN demonstration at OFC2024 by multi-vendor products leveraging photonics-electronics convergence device and open standards

Achieving low latency and low power consumption all-optical connections for distributed data centers

News Highlights:

• At the world’s largest international conference on optical networking technologies, “OFC2024,” a demonstration of an IOWN¹ APN² compatible optical network will be conducted in association with “OFCnet”, which is a cutting-edge technology demonstration environment.
• Collaboration between IOWN Global Forum³ and Open ROADM MSA⁴ demonstrates multi-vendor 400Gbps/800Gbps interoperability, to realize innovative Data Center Exchange service.

Photonics-electronics convergence technology and advanced monitoring technologies enable provisioning of high-capacity services with low latency and low power consumption to the remotely located data center, significantly improving the efficiency of service delivery.

NTT Corporation (NTT) and NTT Communications Corporation (NTT Com) will showcase multi-vendor demonstration of Data Center Exchange (DCX) based on All- Photonics Network (APN) architecture, which is currently being defined by IOWN Global Forum (IOWN GF), by leveraging photonics-electronic convergence devices⁵ that are key to power reduction. This demonstration will take place at 2024 Optical Fiber Communication Conference and Exhibition (OFC2024) in San Diego, USA, from March 26 to 28, 2024 (US time). More compact, intricate cabinet and enclosure designs.

Background

With the penetration of the internet and smartphones, along with the rise of AI services, the communication traffic and power consumption in data centers have been increasing dramatically. To address such a rapid increase in traffic and power consumption, NTT Group is advancing the development and deployment of IOWN APN, a next generation low power and low latency network infrastructure enabled by leveraging photonics-electronics convergence technology. We have a strategy to move away from the concentration of data centers in urban areas to distribute data center building to the suburbs where power and space are readily available. In these distributed data centers connected by IOWN APN, information processing at multiple sites is expected to work as if operating from a single data center location. Therefore, the realization of Data Center Exchange services (DCX) that flexibly connect remotely distributed data centers with high-capacity, low-latency, and low-power consumption end-to-end optical wavelength paths has become a critical need. Such a realization of DCX necessitates the expansion of transmission distances and monitoring scopes to data center sites positioned further away than before. However, current optical networking technologies need to have electrical regeneration to extend transmission distances and monitoring scopes, posing challenges in reducing latency and power consumption. In contrast, IOWN APN aims to expand transmission distances and monitoring scopes without electrical terminations, using end-to-end optical wavelength paths between photonics-electronics devices to achieve the ultimate in low latency and power saving.

NTT Group has been advancing research, development, and field experiments on optical transmission technologies, device technologies, and software technologies required for Open APN, as defined by the IOWN Global Forum (IOWN GF), to realize DCX[1]. In addition, to achieve an open optical network, the collaboration between IOWN GF, Open ROADM MSA, and TIP⁶ is promoting the standardization of network architectures that can be applied for remote monitoring and control at distributed data center sites.

Exhibition Overview

Booth 912 “IOWN Networking Hub” at the OFC exhibition, will showcase DCX, a use case for IOWN APN, using products from multiple companies. DCX by IOWN APN significantly enhances the efficiency of providing high-capacity services to remote locations by offering optical wavelength paths that maintain low latency and low power consumption by eliminating electrical termination within the connection. The demo showcases the solution for remote service provisioning by addressing the technical challenges for remote transmission path monitoring and optimization of optical wavelength paths for long-distance transmission.

End-to-End All-Photonics Network Demonstration:

We will establish high-capacity optical wavelength path (400Gbps and 800Gbps) from/to IOWN Networking Hub using the transceivers with photonics-electronics convergence device. The connection is going through OpenROADM optical network staged by OpenROADM MSA and OpenLab@UT Dallas⁷ at the adjacent booth 916. The collaboration between two booths achieves demonstration of an end-to-end all-photonics network between remote-user sites traversing ROADM-based core domain optical network.

Transmission link characterization and automatic optical wavelength path optimization:

Utilizing remote control agent to enable remote monitoring of equipment deployed in remote data centers by software technologies and Digital Longitudinal Monitoring (DLM)[2] to visualize the power level of end-to-end optical signals for optical wavelength path, we can provide the optical wavelength path with optimal quality on an end-to-end multi-vendor optical transmission network with the latest multi-vendor product.

Open Multi-Vendor Network

The optical networking facilities required for the end-to-end demonstration are built using the network demo environment OFCnet provided by Optica, as well as optical fibers and optical measuring equipment provided by OFS, Anritsu, and VIAVI. Furthermore, by connecting the latest products from leading optical transmission equipment and transceiver vendors such as Ciena, Fujitsu, Molex, and NEC, and utilizing the optical network operation and monitoring systems from NTT Laboratories and NTT COMWARE, an integrated demo has been realized. Additionally, a presentation on the future operational vision of IOWN APN by NTT Com is planned at the booth. The collaboration between IOWN GF and Open ROADM MSA, leading forums in the optical communication industry, showcases an open architecture and the commercialization of necessary key technologies such as photonics-electronics convergence devices, contributing to a diverse ecosystem for the realization of DCX by IOWN. The demo proves it has become possible to establish an open DCX by interconnecting market products of participating companies to build an optical network by adding the monitoring technology provided by NTT Group.

Outlook

Multi-vendor DCX for distributed data centers by IOWN is being realized by the maximum utilization of open standards achieved by open forums such as the IOWN GF, Open ROADM MSA, and TIP. NTT Group is densely collaborating with these forums, aiming for further openness for optical networks as well as enhancement.

NTT Com target to introduce new telecommunication equipment utilizing photonics-electronics convergence technology in Japanese fiscal year 2025, to launch a new communication service such as data center connections, based on further energy-efficient, high-capacity, and low-latency IOWN APN. Additionally, examination has started to deploy advancing technologies such as transmission link characterization and remote monitoring. NTT Group, based on the industry collaboration with multiple companies and forums that made this exhibition possible, will accelerate the application of the energy-efficient, high-capacity, and low-latency IOWN APN to data center connections, which are becoming increasingly vital as social infrastructure.

Note

A part of the demonstration (Remote control agent) is funded by the grant program (adoption number 50201) by National Institute of Information and Communications Technology (NICT), Japan.

^[1] News Release “Establishment and validation of optical wavelength path provisioning technology based on IOWN APN architecture for data center exchange services”, http://group.ntt/en/newsrelease/2023/10/13/231013a.html

^[2] T. Sasai, M. Nakamura, E. Yamazaki, S. Yamamoto, H. Nishizawa and Y. Kisaka, “Digital Longitudinal Monitoring of Optical Fiber Communication Link,” Journal of Lightwave Technology, vol. 40, no. 8, pp. 2390-2408,2022.

¹ Innovative Optical and Wireless Network (IOWN):
IOWN stands for Innovative Optical and Wireless Network, a concept proposed by NTT for networks and information processing infrastructure. Since January 2021, IP Infusion has been a General Member of the IOWN Global Forum (Established in Jan 2020), an international forum promoted by companies and organizations supporting the IOWN vision.
http://www.rd.ntt/e/iown

² All-Photonics Network (APN):
An innovative network based on photonics technology whose architecture is being openly developed by the IOWN Global Forum. The IOWN Global Forum is developing the APN to provide direct optical wavelength paths between any location on demand to implement use cases of the IOWN.
http://iowngf.org/wp-content/uploads/formidable/21/IOWN-GF-RD-Open_APN_Functional_Architecture-2.0.pdf

³ IOWN Global Forum:
A new industry forum that promotes the realization of a new communication infrastructure consisting of all-photonics networks, including silicon photonics, edge computing, and wireless distributed computing through the development of new technologies, frameworks, technical specifications, and reference designs to meet the data and information processing demands of the coming era.
http://iowngf.org/

⁴ OpenROADM MSA:
The OpenROADM Multi-Source Agreement (MSA) is a collaborative effort between carriers and vendors to create and promote an open, disaggregated, and efficient optical networking ecosystem for flexible, scalable, and fully operational networks supporting various services and applications.
http://openroadm.org/

⁵ Photonics-electronics convergence devices:
Devices that combine the electronics and optics technologies to improve performance in terms of miniaturization, economy, high speed and power consumption.
http://www.ntt-review.jp/archive/ntttechnical.php?contents=ntr202401fa9_s.html

⁶ Telecom Infra Project (TIP):
The TIP is a collaborative telecom community. Launched in February 2016, TIP started with the goal of accelerating the pace of innovation in the telecom industry.
http://telecominfraproject.com

⁷ OpenLab@UT Dallas:
Organization established by The University of Texas at Dallas and provided open research environment for optical networking and system interoperability.
http://labs.utdallas.edu/openlab/

The DCX demonstration has been achieved using the following technologies.

1. Remote Optical Connection with OpenROADM/OpenZR+ Transceivers

Transceivers deployed at remote locations utilize two types of standardized 400Gbps signal formats defined by OpenROADM MSA and OpenZR+ MSA⁸. The demonstration setup confirms that transceivers from multiple vendors can interconnect through an OpenROADM network composed of multiple vendors, demonstrating the flexibility of the IOWN architecture from an ecosystem perspective.

For 400Gbps connection with OpenROADM format, the architecture for optical remote connections defined in IOWN GF and OpenROADM MSA is employed, where optical supervisory channel are overlay onto the data signal transmitted to the far end without any electrical termination. Systems and transceivers from Fujitsu and NEC enabled this multi-vendor configuration.

For 400Gbp connections with OpenZR+ format, small form factor transceivers called QSFP-DD⁹, which are compatible with data center equipment, are interconnected between Ciena and Molex products. These transceivers have higher optical output signal level, suitable for transmitting optical signals to more distant locations. Ciena and NTT are leading open standardizations and Ciena implemented the modules to support 14 types of transmission modes defined in open forums like OpenZR+ MSA, OpenROADM MSA, and ITU-T, allowing for the selection of optimal transmission mode per requirements. Molex’s 400Gbps transceiver, powered by IOWN’s photonics-electronics convergence devices, achieves an industry-leading signal optical output of +6 dBm. The end-to-end communication quality is verified using an Anritsu 400Gbps Ethernet tester with two QSFP-DD ports, equipped at the line termination points.

2. Transmission link characterization and automatic optical wavelength path optimization

Traditionally, analyzing the quality of a transmission link required specialized equipment. However, IOWN’s photonics-electronics convergence devices can capture various noises and signal distortions present in the optical transmission link as receiver data. Applying advanced signal processing techniques to the captured optical waveform data enables detailed inspection of the transmission link state using transceivers equipped with photonics-electronics devices, without the need for specialized equipment. The exhibition dynamically showcases Digital Longitudinal Monitoring (DLM), which visualizes the power level transition of the signal light propagating through the optical transmission path, which comprise multiple optical fibers and amplifiers. Additionally, it demonstrates the technology for analyzing and suggesting optimal optical equipment configurations based on the transmission link characterization. Introducing and automating operations with automatic optical wavelength path design technology allows for the agile provisioning of optical wavelength paths between data centers tailored to customers’ environments and usage patterns. These advancements in transmission link characterization and path optimization enable improved efficiency and quality in optical wavelength path provisioning even with the same transmission equipment.

The transmission link characterization technology is implemented on Fujitsu’s 800Gbps transmission system and applied to a multi-stage transmission line built with VIAVI’s multi-ports optical amplifiers and OFS‘s low-loss optical fibers. A demonstration of multi-vendor 800Gbs transmission using the field test bed network built by OFCnet outside the exhibition venue is also planned.

3. Remote control agent

It is necessary to have the remote monitoring and control for optical transceivers deployed in remote locations. Remote control agent, which is a software operating as a container on Kubernetes commonly used in data centers, enables remote operations without imposing any special load on the data center facilities. The demonstration uses NEC’s open 800Gbps transmission system with open NOS (Network Operating System) and open optical muxponder system. NEC’s open muxponder used is compliant with TIP’s Open Optical & Packet Transport (OOPT)¹⁰ Phoenix¹¹, developed with contributions from NTT Labs and NTT Com. The monitoring system employs a proven network monitoring software provided by NTT COMWARE, enhancing the affinity with systems used in data centers and seamlessly integrating remote monitoring functions into the data center’s normal operations.

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