AT&T recently completed testing a 1.6 Tbps carrier wavelength across 296 kilometers of its commercial long-distance network, illustrating the evolving viability of next-generation wavelength technology to be prepared for the growth of AI-based demands.
The 1.6Tbps wavelength carried two IEEE standards-based 800 Gigabit Ethernet end-to-end circuits. It is a complete, uninterrupted data path utilizing a single light frequency across the fiber length between two points.
Mike Satterlee, vice president of network Infrastructure and Services for AT&T, said the company anticipates “network traffic growth to double by 2028, and the technologies demonstrated in this trial will play a key role in AT&T’s continued efforts to keep up with increasing customer demand to send data, watch videos, and use streaming services.”
White box focus
While the advent and use of 1.6 Tbps is still early, what’s compelling about this trial is that it is on a live network route.
Taking place over a 296-km route spanning Newark, New Jersey, to Philadelphia, Pennsylvania, on AT&T’s existing long-haul fiber network, the single-carrier 1.6 Tbps wavelength was transported alongside existing live customer traffic on 100 Gbps and 400 Gbps wavelengths.
Also, AT&T’s trial showcased the service provider’s ongoing movement into software-centric, open-source platforms. White boxes and the disaggregation of hardware and software control costs facilitate faster innovation.
Open-sourced white box switches acted as network equipment during the trial. The white boxes are designed using the Broadcom Jericho3 packet processor chip and can provide up to 18 x 800G network interface ports, all within a 2RU platform.
Meanwhile, the DriveNets Network Cloud software-based solution is hardware-agnostic and runs APIs on the white boxes to perform data and control plane functions, including routing at 800G.
The two 800 GbE signals from the white box were multiplexed to 1.6 Tbps in Ciena’s WaveLogic 6 Extreme coherent optical transponder. This transponder has a 200 Gbaud design and 3nm coherent DSP ASIC and can reach speeds up to 1.6 Tbbs on a single carrier.
Ciena said this trial is the first to demonstrate WL6e at 1.6Tbps with standards-compliant 800 GbE clients.
In the Newark and Philadelphia offices, 800G DR8 pluggable transceivers from Coherent were installed in the white box router and WL6e transponder to create the cross-office connectivity between the packet and optical technologies.
Finally, 800GbE client signals, provided by Keysight’s AresOne-M 800GE test set, fed the white box through additional pairs of 800G DR8 pluggable client optics, allowing verification of end-to-end performance of the two 800GbE services from Newark to Philadelphia.
Wavelength services rising
AT&T’s trial also shows the growing interest in optical wavelength services.
The service provider’s wavelength services offer business and wholesale carrier customers a dedicated high-speed data highway connecting two locations in the same or different metropolitan areas. Using DWDM, multiple high-bandwidth wavelengths can be transmitted in a single fiber strand.
AT&T currently offers speeds from 1 Gbps to 400 Gbps. The telco also offers a private dedicated network with additional options.
Vertical Systems Group said in its Mid-2024 U.S. Wavelength Services LEADERBOARD that what’s driving the need for new optical wavelength services, particularly 100G wavelengths, “is the escalating surge of AI applications as a major purchase driver for 100+ Gbps wavelengths.”
The research firm also noted that customers purchasing 400 Gbps wavelength services include hyperscalers, financial entities, data centers, media and entertainment companies and cloud providers.
Despite the potential of wavelength services, VSG cautioned that U.S. fiber service providers cite very low customer demand for 800 Gbps wavelength services.
For related articles, visit the Business Topic Center.
For more information on high-speed transmission systems and suppliers, visit the Lightwave Buyer’s Guide.
To stay abreast of fiber network deployments, subscribe to Lightwave’s Service Providers and Datacom/Data Center newsletters.
Sean Buckley
Sean is responsible for establishing and executing the editorial strategies of Lightwave and Broadband Technology Report across their websites, email newsletters, events, and other information products.